text:
Frontiers in Marine Science
Ocean Observation
Chris Bowler
École Normale Supérieure, France
Fabien Roquet
University of Gothenburg, Sweden
Shinya Kouketsu
Japan Agency for Marine-Earth Science and Technology, Japan
Data Sets and Validation
Discussion and Summary
Open Supplemental Data
Front. Mar. Sci., 08 December 2015 | https://doi.org/10.3389/fmars.2015.00107
Sea Surface Salinity and Temperature Budgets in the North Atlantic Subtropical Gyre during SPURS Experiment: August 2012-August 2013
Anna Sommer1*, Gilles Reverdin1*, Nicolas Kolodziejczyk1,2 and Jacqueline Boutin1
1LOCEAN/IPSL, Sorbonne Universités (University Pierre et Marie Curie, Univ Paris 06)-Centre National de la Recherche Scientifique-IRD-Muséum National d'Histoire Naturelle, Paris, France
2Laboratoire de Physique des Oceans, UMR Centre National de la Recherche Scientifique/Ifremer/IRD/UBO-IUEM, Brest, France
Variability at large to meso-scale in sea surface salinity (SSS) and sea surface temperature (SST) is investigated in the subtropical North Atlantic Ocean during the Subtropical Atlantic Surface Salinity Experiment Strasse/SPURS in August 2012—August 2013. The products of the Soil Moisture and Ocean Salinity (SMOS) mission corrected from large scale systematic errors are tested and used to retrieve meso-scale salinity features, while OSTIA products, resolving meso-scale temperature features are used for SST. The comparison of corrected SMOS SSS data with drifter's in situ measurements from SPURS experiment shows a reasonable agreement, especially during winter time with RMS differences on the order of 0.15 pss (for 10 days, 75 km resolution SMOS product). The analysis of SSS (SST) variability reveals that the meso-scale eddies contribute to a substantial freshening (cooling) in the central high salinity region of the subtropical gyre, albeit smaller than Ekman and atmospheric freshwater (heat) seasonal flux, which are the leading terms in SSS (SST) budget. An error is estimated along with SSS and SST budgets; as well as sensitivity to the different products in use and residuals are discussed. The residuals in the SSS budget are large and can arise from errors in the advection fields and freshwater flux, from neglected small scale or unresolved local processes (salt fingering, vertical mixing, and small scale subduction, etc.). However, their magnitude is similar to what is often parameterized as eddy horizontal diffusion to close large scale budgets.
The water cycle is a predominant element of the Earth's climate which has a specific impact on human society among agriculture, energy and water supply. In the global water cycle, the ocean plays a key role, with ~86% of global evaporation and 78% of global precipitation taking place over the ocean (Schmitt, 1995). Despite growing observing capability, in particular from satellites, our knowledge of precipitation (P) and evaporation (E) over the oceans is still rudimentary (Trenberth et al., 2007; Skliris et al., 2014; Durack, 2015). It is due to coarse available in situ measurements and insufficient sampling or systematic errors in satellite retrievals.
The climatological mean of sea surface salinity (SSS) is closely related to the surface E-P flux (Schmitt, 1995; Durack, 2015). Thus, as the ocean salinity is better observed than P or E, its monitoring could also contribute to better understand the pattern and variability of the E-P field. Large salinity trends or multi-decadal variability have been observed in large parts of the world ocean in the last 30–50 years (Durack and Wijffels, 2010; Terray et al., 2012; Skliris et al., 2014). They provide sharper information about a changing global water cycle than terrestrial data (river flows, evaporation or precipitation) which show less trends (Dai et al., 2009; Lagerloef et al., 2010).
The changes in salinity concentration originate from precipitation, evaporation, runoff, ice freezing and melting, as well as changes in ocean circulation and mixing (Talley, 2002). Thus, the ocean dynamics needs to be accurately assessed to link E-P field's variability with change in SSS (Yu, 2011). At meso-scale, recent work in the North Atlantic subtropical gyre (Qu et al., 2011; Busecke et al., 2014; Gordon and Giulivi, 2014; Farrar et al., 2015) shows a significant contribution of horizontal advection in governing surface salinity, with roughly half of the salinity variation being explained by ocean meso-scale dynamics. In the South Pacific, the compensation of fresh water loss is also made by vertical turbulent mixing and horizontal salinity advection (Hasson et al., 2013; Kolodziejczyk and Gaillard, 2013). However, in these studies, the respective contribution of meso-scale advection and vertical mixing is not very well established because of uncertainties in the data sets and also because of the crude horizontal resolution.
In this work we concentrate our investigation on near-surface salinity and temperature budgets in the saltiest region of the world open ocean, the sub-tropical gyre of the North Atlantic Ocean (NSTG, Figure 1). In this region, evaporation is a dominant component of the salinity budget, as shown in the E-P climatological map. The eastern subtropical North Atlantic surface area is affected by dry continental air from North Africa. To balance this water loss due to the excess of evaporation flux, fresh water transport is contributed by eddies, mixing processes, and Ekman transport (Gordon and Giulivi, 2014). The Ekman transport from the tropics is large in this region and brings fresh and warm surface water from the tropics, while further north a weaker Ekman transport brings fresh and cold water. The vertical entrainment of deeper water is expected to be a major contributor to the salinity (Dong et al., 2015) and temperature change in particular during the winter. At large-scale, the change of SSS in salinity maximum region is small compared with the amplitude of the sea surface forcing and "residual terms" (subduction, vertical shear, vertical motions, internal waves and all small-scale and fast dynamics, Dohan et al., 2015) that close the budget. Furthermore, Dong et al. (2015) found that for the SSS (or fresh water) budget the Ekman component dominates the total horizontal advection in this North Atlantic region. On the other hand, at the scale of turbulent advection, it is worth to note that the Ekman transport does not play a significant role. The turbulent advection is indeed mainly responsible for the freshening and warming/cooling by eddies (Busecke et al., 2014).
Figure 1. North Atlantic subtropical region, January 2013. Climatological monthly mean SSS from SMOS and Ekman velocity field using ERA-Interim. The black box indicates SPURS region. The red box is the region that was chosen for estimation of salinity budget. Black cross is the mooring position at 24.5°N 38°W.
To estimate a regional surface salinity budget during the period August 2012–2013, surface salinity product derived from the Soil Moisture and Ocean Salinity (SMOS) satellite mission, a regional ocean current product produced by AVISO and in situ data collected during the SPURS (Salinity Processes in the Upper-ocean Regional Study) experiment are used. The SPURS experiment took place in August 2012–April 2013 (Figure 1, black box). Its goal was to better understand the mechanisms responsible for salinity maximum formation in the subtropical North Atlantic (Oceanography special issue, 2015, Vol. 28, No. 1). The drifter data collected during SPURS and afterwards are used to validate the SMOS derived SSS and the ocean current products. The SST budget is estimated based on the OSTIA (Operational Sea Surface Temperature and Sea Ice Analysis) data. The SST budget is investigated to compare the meso-scale contribution in this budget to the one in the SSS budget, and better understand their effect on the SSS budget.
We will first describe the data sets and their accuracy in Section Data Sets and Validation before discussing the methodology in Section Method. Results and their discussion are then presented in Sections Results and Discussion and Summary respectively.
We investigate the area of 21°−30°N 50°−26°W. In the next section we will explain why we consider this region.
Spurs Drifters
The SPURS international experiment took place over one seasonal cycle during 2012/2013 (Figure 1, black box). Around 150 drifters were deployed in the central NSTG mostly in August–October 2012 and March–April 2013 (Centurioni et al., 2015). SVP-S drifters (Lumpkin and Pazos, 2007; Reverdin et al., 2007; Centurioni et al., 2015) have a battery pack, a satellite transmitter, a conductivity sensor below the surface float as well as a sea surface temperature (SST) sensor located either next to the conductivity cell or at the base of the float to avoid direct radiative heating. The drifters initially have a drogue centered at 15 m to follow the currents at this depth. Most of the drifters had a sensor to identify the presence of the drogue. In this work we use data of drogued SVP-S drifters. The time step of the data records is usually 30 min.
Mooring Data
The surface mooring was deployed as part of the SPURS project by the Upper Ocean Processes Group at WHOI at ~24.5°N 38°W (Figure 1, black cross). Data was collected from September 2012 until September 2013 by the ASIMET (Air-Sea Interaction Meteorology) system. The ASIMET system provides measurements of specific humidity, SST and conductivity, wind speed and direction, barometric pressure, shortwave radiation, longwave radiation, and precipitation. These variables are used to compute air-sea fluxes of heat, moisture and momentum using bulk flux algorithm. The accuracy of the mooring data is 8 Wm−2 for the heat fluxes, 6 cm yr−1 for the evaporation and 10% for precipitation (Colbo and Weller, 2009; Farrar et al., 2015). We use these mooring data to validate the gridded data sets of heat fluxes, evaporation and precipitation.
The SMOS satellite mission was launched in November 2009 on a sun-synchronous circular orbit with a local equator crossing time at 6 a.m. on ascending node and at 6 p.m. on descending node. The SMOS mission carries an L-band (1.4 GHz) interferometric radiometer that allows the reconstruction of a bi-dimensional multi-angular image of the L-band brightness temperatures (Tb) that is used to retrieve the SSS (Kerr et al., 2010).
In the subtropical North Atlantic SMOS SSS suffers from a seasonally varying systematic error (Hernandez et al., 2014), especially strong during boreal winter (RMS close to 0.5, Figure 2). Systematic errors in SMOS SSS originate mainly from inaccuracies in instrument calibration, in image reconstruction (in particular the one that depends of the distance to coast, Kolodziejczyk et al., 2015a) and from anthropogenic RFI (Radio Frequency Interferences).
Figure 2. RMS differences at drifter positions (in pss) over the SPURS domain between drifters SSS and 10-day CEC-CATDS SMOS SSS product (black), SMOS-OI with (green) SSH or without (red) constraint.
In this work we use a new corrected and optimal interpolated (OI) SMOS SSS products described in Kolodziejczyk et al. (2015a,b, submitted), providing SSS to 75 km and 10 days resolution. The new OI SMOS SSS are derived from ESA level 2 SSS v550, using the same flagging as Boutin et al. (2013). The correction for systematic errors follows a two-step procedure: (1) removal of systematic errors in the vicinity to coast; (2) removal of seasonal systematic errors. First, data are corrected for 4-year mean (07/2010–07/2014) near coastal discrepancies with respect to the ISAS Argo climatology (Gaillard et al., 2009) taking into account that systematic errors depend on the location of the pixel across track and on the orbit orientation. Then, ascending and descending orbit data are mapped separately with an optimal interpolation scheme at large scale (500 km) with a Gaussian shaped correlation function. The seasonal large scale biases are then derived from the comparison with monthly ISAS SSS products. The last step is a noise reduction and mapping of bias corrected SMOS SSS every 7 days on the regular grid of 0.25° using optimal interpolation with a Gaussian correlation function scaled to 75 km over a window of 10 days centered on the day of mapping, using the corresponding monthly ISAS SSS fields as first guess.
In order to improve the horizontal SSS gradient at meso-scale, we also tested the introduction of a small constraint on along-stream-line (from AVISO SSH) orientation of the structures by including it in Gaussian correlation function (Kolodziejczyk et al., 2015a). This method allows to recover spatial scales slightly smaller than 75 km (OI SMOS SSH).
The SMOS OI (Figure 2, red curve) shows significant improvement with respect to earlier products (Figure 2, black curve, original SMOS product). The RMS difference between SMOS SSS at 10 days 75 km resolution and in situ data (TSGs, drifters) is lower than 0.15 almost for the whole period. The introduction of the supplementary correction (OI SMOS SSH) marginally, not significantly, improves the results (Figure 2, green curve). In this work we retained this last version of the weekly SMOS products with the spatial resolution of 0.25°.
As expected from the error statistics, the mapped (OI SSH) SMOS SSS field with the drifters' trajectories and data overlaid for the week 8–14 January 2013 (Figure 3) suggests that remaining systematic errors are small, and that the product captured a good part of meso-scale variability. Further discussions of the characteristics of the mapped product will be provided in another paper.
Figure 3. SMOS SSS vs. SPURS drifters and AVISO geostrophic velocity field, 8–14 January 2013.
From Figure 2 we just note that the error budget seems to remain relatively stationary in time. The small RMS error during August 2012 (Figure 2) results from a too small number of data for this period. There is a small peak of larger RMS difference in the week between January and February 2013 which could be due to a rain/wind front across this area inducing larger spatial variability and/or errors. Indeed, the rain front could have generated rapid and small scale wind changes not well captured in ECMWF (European Centre for Medium-Range Weather Forecasts) wind forecasts that are used in the SSS retrieval scheme.
Sea Surface Temperature OSTIA
To estimate the SST we use daily OSTIA SST analysis with horizontal resolution 0.05° (Reynolds and Chelton, 2010; Donlon et al., 2012). The SST product from OSTIA has zero mean bias and an accuracy of ~ 0.57 K compared to the in situ measurements as noted in Donlon et al. (2012).
AVISO Altimetry
A regional AVISO 2014 altimetric product (daily product with 1/8° spatial resolution) was chosen as the geostrophic velocity field (Dussurget et al., 2015, D15 product). Compared to the standard Ssalto-Duacs product, it uses less along-track filtering, which is optimized in this region and for the different satellites. It uses also an updated Mean Dynamic Topography (MDT). This product was validated with the drifter data. The ocean currents from this product fit reasonably well the drifter trajectories (example in Figure 3) and seem to be associated with deformations of the large scale SSS fields. Salinity gradients tend to align along the streamlines. For example, in the north of the area, there is a small advection of fresh water in salty region at 27°N 46°W that is explained by geostrophic AVISO currents. The eddies inside the high SSS area usually correspond to local SSS maxima or minima: 22°N 34°W, 23°N 30°W, or 26.5°N 44°W.
We estimate MLD on individual Argo temperature-salinity profiles (Gould et al., 2004). The MLD is estimated, when a threshold value for either temperature or salinity is attained compared with a near-surface value at 10 m depth: ΔT = 0.10C, ΔS = 0.03pss. We group these estimates monthly to provide a monthly mixed layer depth distribution (in the standard case, it is the average of the distribution that is retained). We use data from Coriolis web site with the flag "good data." Because of insufficient data distribution, we only use them as providing a large scale average. The comparison (Figure 4) with the monthly gridded ISAS (In Situ Analysis System) fields (spatial resolution 0.5°), an optimal estimation tool designed for the synthesis of the Argo global data sets (Gaillard et al., 2009), at the Argo profile positions (blue curve) and averaged over the domain (green curve) shows a shallower MLD than the Argo data (red curve) throughout the year, with the maximum difference of ~25 m in December. The interpolation of Argo data can smooth the local MLD deepening, especially in December when there are more local rain events in this region. The consideration of the MLD in different latitude bands (Figure 4, red dashed curves) shows a horizontal gradient (from shallower MLD in the South to deeper in the North) and different restratification time (March in southern regions and March-April in northern regions; Kolodziejczyk et al., 2015c).
Figure 4. MLD from Argo (red) and ISAS interpolated product (blue and green) for period August 2012—August 2013. MLD from Argo profiles for different latitude bands (red dashed lines).
Atmospheric Fluxes
Freshwater Flux
Daily Era-Interim reanalysis from ECMWF (spatial resolution 0.25° × 0.25°), widely used daily OAFlux product (1° × 1°) from Woods Hole Oceanographic Institution (WHOI) for evaporation field and daily Era-Interim reanalysis, TRMM TMI (3B42) (0.25° × 0.25°) and GPCP (1° × 1°) satellites for precipitation field were tested. GPCP is strongly based on satellite retrievals, such as TRMM TMI, and surface rain gauges (Adler et al., 2012).
The comparison of evaporation field from Era-Interim (Figure 5A), black curve) with ones from OAFlux (Figure 5A), blue curve) indicates small differences between ~0 and 0.5 mm/day. The comparison with the mooring data at 24.5°N 38°W (see 2.2, Figure 5A), low-passed filtered data with 30 days cut-off) shows that ERA-Interim product sometimes (October, November, June) overestimates evaporation (max ~0.5 mm/day) but usually in the confidence interval from the mooring data (0.16 mm/day) with a high correlation, while OAFlux product underestimates a little (max ~0.7 mm/day and it is out of the mooring confidence interval in spring and summer) evaporation during almost the whole period. This is in line with the expectation that OAFlux might slightly underestimate the evaporation (from ERA-Interim and buoys) in the subtropical gyre of the North Atlantic (Yu et al., 2008).
Figure 5. (A) —Evaporation (ERA-Interim—black curve, OAFlux—blue) and precipitation (GPCP—red, TRMM—orange, ERA-Interim—green) data averaged over the month and over the domain (solid lines) and evaporation filtered with cut-off period 30 days at mooring position 24.5°N 38°W (dashed lines, mooring data—gray curve); (B) —precipitation data at mooring position.
On the other hand, Era-Interim reanalysis produces larger precipitation events over the North Atlantic compared with the satellite data (Figure 5A), green curve). TRMM satellite precipitation (Figure 5A), orange curve) is stronger than one from GPCP (Figure 5A), red curve) (Huffman et al., 2001). The comparison with the mooring data does not show a good agreement between the different products, even after monthly averaging (Figure 5B). ERA-Interim shows much higher total precipitation (2.58 mm/day) compared with mooring data (1.86 mm/day ± 10%), TRMM overestimates high precipitation events (total precipitation 2.76 mm/day). GPCP does not correlate well with the mooring time series, but presents a very close total precipitation average (1.69 mm/day). We retain GPCP in this work.
Heat Fluxes
The latent heat, sensible heat, net downward short and long wave radiations from ERA-Interim with the resolution 0.25° × 0.25° are used to estimate the surface heat flux. ERA-Interim net surface heat flux presents a satisfactory agreement with the one from mooring data at 24.5°N 38°W (Figure 6). The average over the year for the incoming short wave radiation is 220.3 Wm−2 with mooring data and the net downward short wave radiation is 252.06 Wm−2 with ERA-Interim, for the long wave radiation it is respectively −58.84 W/m2 and −58.9 Wm−2, for the sensible heat flux it is respectively −6.37 Wm−2 and -13.19 Wm−2, and for the latent heat flux it is −124.08 Wm−2 and −144.37 Wm−2 respectively, so that the net heat flux across the sea surface of the two products differ by less than 6 Wm−2.
Figure 6. Surface heat flux for the period September 2012–August 2013; solid curves—ERA-Interim reanalysis, dashed curves—mooring data at 24.5°N 38°W, red—net short wave radiation, green—net long wave radiation, blue—latent heat, orange—sensible heat.
We consider the ML salinity (MLS) budget that can be written as (based on the conservation equation of any tracer with additional scale separation) (Delcroix and Hénin, 1991):
∂〈S〉∂t=−〈u′∇S′〉−〈u¯∇S¯〉−(S10 m−S−entr)h(∂h∂t+〈w−h〉) +〈(E−P)Sh〉+R, (1)
where <S> denotes SSS averaged over the domain for each time step (month), S is the mean salinity over a 90 days period for each grid point, u = ū + u′, h is MLD averaged over domain, w−h is the Ekman vertical velocity calculated with the Era-Interim wind, u is the horizontal velocity vector, the sum of geostrophic AVISO velocity field and Ekman velocity that was calculated as τ→ρfh, (E-P) is the difference between evaporation and precipitation. In term of entrainment S10m is the salinity at 10 m depth (that is considered as the salinity of MLD), S−entr is the salinity of the entrained water and is estimated as the salinity at the depth (∂h∂t+w-h)×ΔT, (with ΔT = 1month ≈ 2592000s) that scales the layer of entrained water during the month considered (a month is the elementary time step in the mixed layer depth analysis). The left side of the equation presents the MLS tendency. The first term of the right side of the equation is turbulent horizontal advection estimated at each grid point and then monthly averaged over domain; the second one is mean horizontal advection estimated as the previous term. The third term presents the entrainment component (here we used Argo profile salinity, and neglect horizontal gradients when estimating this term as the MLD was chosen the same over whole domain for the considered month). The fourth term is the surface forcing that was estimated in the same manner as advection terms. The last one R is residual term that includes the sum of all unresolved physical processes and the accumulated errors from the other terms.
Similarly, the ML temperature (MLT) budget can be written as Moisan and Niiler (1998):
∂〈T〉∂t=−〈u′∇T′〉−〈u¯∇T¯〉−(T10 m−T−entr)h(∂h∂t+〈w−h〉) +〈(Q)ρCph〉+R, (2)
where <T> is SST averaged over the domain for each time step (month), Q is the surface heat flux, C−p is the specific heat capacity, ρ is density, all other terms are the same as for salinity budget. The surface heat flux can be calculated as Q = Ql + Qs + Qlw + (1 − α)Qsw[1 − I(h)] (Morel and Antoine, 1994; Sweeney et al., 2005), where Ql is latent heat, Qs is sensible heat, Qlw is net long wave radiation, Qsw is net short wave radiation, α = 0.04 is the ocean surface albedo, I(h)=Re-h∕D1+(1-R)e-h∕D2 is the penetrative solar irradiance with the fraction of total solar flux for wavelengths longer than 700 nm R = 0.58, it is assumed to penetrate the ocean with a decreasing exponential profile, with an e-folding depth scale D1 = 0.35m; D2 = 23m is the second extinction length scale associated with the shorter wavelength (Madec and the NEMO team, 2014).
All data sets were interpolated to the OI SMOS grid with the spatial resolution 0.25 × 0.25°. The error bars for each term were estimated by propagating the errors on the data (Appendix B in Supplementary Material).
We chose the region within the latitudes/longitudes range 21°−30°N/50°−26°W in subtropical Atlantic salinity maximum. It encompasses the region of largest SSS and strong SSS horizontal gradients just out of the domain (Figure 7A). In particular in the south one expects the strong SSS gradient due to a very large contribution from Ekman currents. Moreover, there is a large eddy variability in the North and in the West where the annual mean of SSS variability ∂〈S〉∂t reaches more than 0.6 pss/yr which is two times higher than in the center of the box (Figure 7; on the southern and eastern boundaries we are limited by the availability of the regional AVISO data). On Figure 7B (the annual mean of the turbulent salinity advection) the strong effect of eddy variability is further north, south and west (out of the domain), where it shows higher maximum absolute value larger than 0.6 pss/yr almost everywhere for these regions. On Figure 7C (the annual mean of the mean salinity advection) one notes the strong effect of Ekman currents further north and south up to 0.75 pss/yr. Furthermore, the spatial concentration of drifters and Argo data is larger in the center of the region and used to check the realism of the analysis.
Figure 7. Terms of the Equation (1) averaged over the year August 2012—August 2013; (A) —time salinity change, (B) —turbulent advection term, (C) —mean advection term.
Salinity Budget
As mentioned before, SSS maximum is located a few degrees to the north of the E-P maxima (Figure 8) which shows the importance of the ocean dynamics in this region (Qu et al., 2011), indicating in particular a contribution of Ekman advection, and suggesting a large scale balance between sea surface forcing, advection and mixing processes. In winter 2012–2013 (especially in December) a rain band was found in the middle of the region which resulted in two local maxima on Figure 8B.
Figure 8. Annual salinity (A) and E-P (B) mean with the selected region for SSS budget estimation (red box) over the August 2012—August 2013.
The terms in Equation (1) were estimated and averaged over the whole domain (Figure 9A). As expected, there is a strong response of the surface ocean to the evaporation flux (blue curve) on the salinity change term (green curve). The error bar is large during autumn and early winter months. This is due to local precipitation events and fast temperature changes, as consequences the evaporation changes that are not well reproduced.
Figure 9. (A) —components of salinity budget, residual (black dashed curve) and the sum of all estimated components of the right side of the Equation (1) (black curved); (B) —entrainment (orange curve) and Argo MLD (red); (C) —salinity change (green) and advection components (red).
The entrainment term contributes only during autumn and winter months when MLD is deepening (Figures 9A,B), orange curve). During the winter months entrainment plays a smaller role as the deepening of the ML is weaker and the MLS is closer to the salinity that is found deeper (S−entr). In November when there is a small increase in the surface forcing term (evaporation increases) salinity continues to lower due to entrainment. In December, a month with larger amount of precipitation and small entrainment, the salinity changes are predominantly governed by surface freshwater flux (Figure 9A). Due to the difficulty in estimating the error on entrainment, only the error bars (standard error) on MLD is shown (Figure 9B).
For the whole domain the spatially averaged advection is negative throughout the year with a relatively small amplitude (Figures 9A,C). The turbulent and mean advections are both negative with the stronger magnitude for the mean component. It shows a moderate seasonal cycle associated with a maximum freshening during summer.
The sum of all estimated equation's component in the right side of the Equation (1) (here and after does not include R) (Figure 9A), black curve is very close to the surface forcing term and its difference with ∂〈S〉∂t gives a large residual term R (Figure 9A), black dashed curve.
To better understand the effect of advection we separate the region into two boxes: 21°−25.5°N 50°−26°W and 25.5°−30°N 50°−26°W. The dividing latitude was chosen based on the seasonal means and seasonal variability maps of the equation's terms (Figure 10). During the winter, the SSS variability term (Figure 10A) is characterized by salinity decreases north of 25.5°N, while a region with variable salinity changes (salinity can increase as well as decrease) is found in the South. For the SSS variability in the summer season (Figure 10B) the latitude 25.5°N separates a region of dominant increase in the North from a dominant decrease in the South. It means that during the summer the strong increase of SSS takes place in the northern region, while during the winter there is the largest decrease. Autumn and spring (not presented) show similar patterns for these two regions. The advection variability maps (Figures 10C,D) show two different structures in the southern part. During autumn (Figure 10C) some freshwater originating from the Amazon basin enters this region and is mixed through the domain, inducing a strong variation of turbulent advection in the south-western part (the std is up to 10 pss/yr in this region). During spring (Figure 10D) mean advection plays a significant role in the salinity change with significant spatial variability both in the northern as well as in the southern parts. Surface water flux (Figures 10E–G) shows strong spatial variability in both regions during the autumn (Figure 10E) and in the South during the spring (Figure 10F) when evaporation largely dominates there. The mean surface forcing (Figure 10G) also exhibits different regime on either side of 25.5°N that isolate the southern region, the region of maximum E-P field. Thus, 25.5°N separates two regimes in the SSS budget variability in agreement with Dong et al. (2015).
Figure 10. Sea surface salinity change in winter (A) and summer (B). Turbulent advection standard deviation in autumn (C) and mean advection standard deviation in spring (D). Surface forcing standard deviation in autumn (E) and spring (F) and surface forcing mean in summer (G).
In the southern part, both the turbulent advection and mean advection (Figure 11A) play a significant role during the autumn and brings fresh water through eddy transport. On the other hand, during spring and summer it is rather the mean advection that brings freshwater from the tropical regions. In the northern part (Figure 11B), advection does not show significant variability throughout the year except during summer when mean advection brings the salty water from the south and contributes to the salinity increase. In general, the domain-averaged salinity presents large month-to-month changes throughout the year (intraseasonal variability) in the southern part (Figure 11C) and seasonal cycle in salinity in the northern part (it decreases in winter and increases in summer). In the southern part, SSS decreases until October due to the small surface forcing, the effect of the advection and the entrainment terms. Afterwards there is a salinity increase in November. At this time the surface flux continues to decrease and the advection terms diminish in absolute value and reduces its freshening effect on the salinity. At that time even strong entrainment cannot significantly refresh the surface water. In December the salinity again decreases while freshwater flux increases, the entrainment starts to be smaller and there is only a small decrease in advection term that cannot match this strong change in salinity. Thus, in this month other processes contributing to the much larger residual term probably increase.
Figure 11. Salinity change (green) and advection components (red) (A,B) and components of salinity budget, residuals (black dashed curves) and sums of right side's estimated equation components (C,D), Equation (1). (A,C) −21°−25°N, (B,D) −25°−30°N.
During the summer months, the salinity change is controlled by advection associated with transport of fresher water from the tropics that partially counterbalances the gain from evaporation. In the northern domain (Figure 11D) during winter the salinity change is strongly influenced by entrainment of deeper water and horizontal advection that contribute to a decrease of SSS. One of the two local minima of the residual component is found at this time.
In summer, the salinity increase strongly depends on advection which brings salty water from the E-P maxima region, and freshwater flux which concomitantly increases. The residual terms are large and in the range from 0 to −1.5 pss/yr in particular for the southern region.
Heat Budget
The estimation of the temperature budget based on Equation (2) in the subtropical gyre of the North Atlantic (Figure 12) indicates a near-balance between the terms retained, i.e., the error bar range of the two sides of the equation overlap [black solid (the sum of all elements in the right part of the Equation (2)] and green (temperature change) curves). The different components of the temperature budget have the same pattern irrespective of the domain [total region (Figure 12A), southern (B) and northern (C) parts]. SST (green curve) decreases in late autumn and winter and increases in spring and summer. The term of surface heat flux (blue curve) shows comparable variability in the two regions being largely responsible for the temperature change. The entrainment term (orange curve) is large during late autumn and winter and contributes to lower SST. Only the terms of horizontal advection are different for the southern (Figure 12B) and the northern (Figure 12C) parts. In the southern part, advection is negative throughout most of the year, bringing colder water mostly from the North, whereas it is positive during spring and late summer, the period of large warming. In the northern part the sign of advection is the same, except for November and December with a positive advection term. It implies that during these 2 months the horizontal gradient of SST was small over the region. After this period the colder water comes from the North and the East, resulting in negative advection terms. As commented the net residual terms are relatively small with an annual negative average.
Figure 12. Components of temperature budget for the period August 2012–2013, residual (black dashed curves) and the sum of all estimated components of the right side of the Equation (2). (A) —total considered region; (B) —southern part 21°–25°N; (C) —northern part 25°−30°N.
We examined the salinity and temperature budgets in the subtropical gyre of the North Atlantic 21°-30°N/50°-26°W during the period August 2012–2013 based on the OSTIA data for SST and CATDS CEC LOCEAN SMOS corrected data (OI SMOS and OI SMOS SSH) for the SSS. The OI SMOS SSS gives promising results, as a comparison with drifter data shows RMS differences on the order of 0.15 even in winter; the introduction of a constraint coming from SSH marginally improves the results. The spatially-averaged SSS presents a realistic seasonal cycle with the minimum in winter and maximum in summer (Figure 9A), as is also found for SST (Figure 12). This region contains an Ekman convergence zone around 25.5°N which results in two different regimes within the box. The division of the region into two parts shows that in the southern part of the domain SSS does not present a seasonal cycle. In this region the freshwater flux is partially balanced by other terms of the salinity budget while in the northern region the effect of the freshwater flux is dominant. The SST budget presents a similar variability in the southern and northern parts. The gradient of SST changes sign on the diagonal (from South-West to North-East) of the box compared with the meridional gradient of the SSS. The effect of warm water from the equator is first felt in the southern part during early spring with an earlier and faster increase of SST than in the northern domain.
The freshwater flux is the dominant component in the salinity budget (0.88 ± 0.3 pss/yr, averaged over the period September 2012 – July 2013 and over 21°−30°N/50°−26°W region) while the heat flux (2.9 ± 1.34 C°/year; for the 13 month period it is 4.12 ± 1.43 C°/year) is the dominant component in the temperature budget. Both of them have a seasonal cycle with a minimum in winter and maximum in summer. The heat flux is responsible for the variability in SST throughout the year. SSS and SST do not show a strong tendency 0.014 ± 0.2 pss/yr and 1.5 C°/yr over these 11 months, similar to the results averaged over the 10-years (2004–2013) period and over the SPURS-1 region in Dong et al. (2015) (for salinity). Dong et al. (2015) have found a 1-month lag between the salinity change and the seasonal cycles of surface forcing term, which might be the result of a slightly different region retained in their analysis [notice that Dong et al. (2015) domain is 5° further south than the region in Figure 1 (red box)].
The advection term depends on the scale, region and time period. Farrar et al. (2015) shows the strong influence of advection at the meso-scale, whereas in Dohan et al. (2015) the large-scale advection term is small compared with the amplitude of the sea surface forcing and is referred to as "residual term." Dong et al. (2015) have shown that the Ekman and geostrophic advection mean state component nearly compensate each other in the region 20°−30°N 45°−30°W. In the region that we retained we find that the advection term (Figure 9A, red curve) does not present a large seasonal variability and contributes to a negative (freshening) effect on the total budget (−0.16 ± 0.02 pss/yr in our work to be compared with Dong et al. (2015) −0.28±0.01 pss/yr for the period 2004–2013 and over the larger region). The mean part of the advection term plays a dominant role in the salinity budget in the subtropical gyre of the North Atlantic (the mean part equals −0.11±0.02 pss/yr whereas the turbulent part equals −0.04±0.02 pss/yr). In the two sub-regions the role of the advection terms starts to be clearer: (1) the effect of the turbulent advection component is important in the southern part during the autumn when it contributes to a freshening; (2) in spring and summer Ekman advection brings fresher water from the equatorial zone to the southern part of the domain, whereas its salty water from the E-P maximum region is transferred further North where it contributes to the salinity increase; thus it explains the strong contribution of mean component in the southern region, −0.18±0.04 pss/year and −0.06±0.04 pss/year for the turbulent component. In the temperature budget the value of the averaged advection term over the period and domain plays a small negative (cooling) role (−0.04±0.02 C°/yr) as the values of the mean and turbulent advections are −0.16±0.02 C°/yr and 0.12 ± 0.02 C°/yr, respectively. This suggests that the turbulent advection has a strong positive effect (warming) than mean advection but the turbulent component is still small compared with the other terms while the mean term varies throughout the year which "compensate" when averaged over the year (not shown).
The entrainment component plays a role during autumn and winter when mixed layer deepens. In the salinity budget this term has a modest effect (−0.15 pss/yr) while in the temperature budget it is the major component that compensates the effect of the heat flux (−3.58 C°/yr).
Despite the physical consistency of the results, the salinity budget cannot be closed. The surface forcing term has a strong influence on the salinity and temperature budgets. Errors on this term induce errors in the salinity budget estimation as suggested by the fact that the residual terms (Figures 9A, 11C,D, 12) tend to mirror the freshwater flux terms. Furthermore, the error bar on freshwater flux (resulting from time-space variability) exceeds 0.6 pss/yr in autumn and spring/summer seasons, the periods where the residual term is large. In the autumn, there is also the possibility that the precipitation might not be correctly estimated, whereas in the summer months, the comparison with the mooring data suggested a possible overestimation of evaporation in the ERA-Interim reanalysis used here.
The error bars on advection terms are small but in some region the AVISO product underestimates the geostrophic velocity (comparison with surface drogued drifters, unpublished results). This later effect could change our results a little but probably not significantly as the results for the temperature budget (Figure 12) with the same data sets show a much closer budget. There is however also for that term the possibility that the SMOS-product that we used presents too large errors or smooths out some of the scales responsible for the meso-scale advection (but see Appendix A in Supplementary Material, which suggests that at least at 0-order it produces a reasonable estimate).
The errors are also sensitive to the MLD chosen. In order to estimate entrainment we use the MLD averaged over the domain. This approach excludes the consideration of the horizontal gradient, and salinity change by induction which may be not negligible in the area (see for example Dohan et al., 2015; Dong et al., 2015). This contributes to uncertainties in our results, and obviously misses more local and smaller scale processes. At this point the data used do not allow to evaluate the effect of a spatial change in MLD at meso-scale. But the fact that this method gives good results for SST budget means that the SSS is more sensitive to the vertical processes such as restratification, mixing and etc.
Altogether we find large residuals from the salinity budget ~−0.3 pss/yr (or 47% of the average modulus of ∂〈S〉∂t which varies in the range ±0.63 pss/yr), whereas they are much smaller for the temperature budget, also with a negative average, −0.77 C°/yr (~4% of the average magnitude of ∂〈T〉∂t which varies in the range ±18 C°/yr) (see Table 1). It is probably due to the strongest effect of the heat flux on the temperature change that simplifies the estimation of temperature budget, while the salinity variability strongly depends on the ocean dynamics (Figure 8). The advection is the most important component for the salinity budget in this region and can be the main source of errors due to the uncertainties in salinity field and underestimation of velocity field that was discussed above. Moreover it is thus difficult to blame a choice of a too shallow mixed layer in the summer months, as it would contribute to a negative residual in the SSS budget, but also in the SST budget. Small scale processes such as are found near filaments or fronts, could be a source of asymmetry between the SST and SSS budgets. Indeed, in the southern part of the domain, Kolodziejczyk et al. (2015c) showed that SSS spatial variability dominates the surface density gradients. This was also witnessed in summer during the Strasse cruise (Reverdin et al., 2015), and in early spring during the Midas cruise (Busecke et al., 2014). Dynamical processes that induce mixed layer restratification would thus contribute to an average SSS decrease, but with little notable effect on SST (Shcherbina et al., 2015). In addition, vertical mixing with salt fingering at the lower boundary of the mixed layer would also contribute to a larger SSS negative term compared with SST, but this would happen preferentially when there is a large salinity vertical stratification compared to temperature, and thus probably not in the summer months. In some studies the mismatch (residual) is parameterized by eddy horizontal diffusion terms, as in Dong et al. (2015) when such a term contributes to the MLS changes with the averaged magnitude of −0.28±0.01 pss/yr thus comparable with our residual term (−0.3 pss/yr).
Table 1. Annual averaged means of the components in Equations (1) and (2).
Using other data sets (for precipitation, evaporation, MLD, etc.) to estimate the salinity budget could help better understand the mechanism of formation of the salinity maximum of the subtropical North Atlantic and its seasonal variability. Further testing other ways to estimate entrainment or a relevant mixed layer depth would also improve the reliability of these results. In further work we will also estimate the SSS and SST budget based on Mercator PSY2V4R4 simulation data to improve the entrainment estimation method, to validate the model data on the meso-scale and to estimate subscale horizontal diffusion and impact of vertical processes.
AS has done the analysis of the budgets of surface temperature and salinity in the North Atlantic subtropical gyre during SPURS experiment. GR is the Thesis supervisor of AS. He tested the salinity drifters and contributed to their operation during SPURS. He is the French PI in SPURS experiment. NK has characterized meso-scale variability in surface salinity from SMOS band-L radiometer remote sensing data. JB is the specialist on band-L radiometry data and a SMOS-mission French PI. She also contributed to the supervision of AS.
The authors thank the two reviewers for their helpful comments. The authors thank the CLS team who work on the regional AVISO altimetry product: R. Dussurget, S. Mulet, M.-I. Pujol, M.-H. Rio. The original altimeter products were produced by Ssalto/Duacs and distributed by AVISO, with support from CNES (http://www.aviso.altimetry.fr/duac). SVP drifters were provided by the Global Drifter Program, NOAA grant #NA10OAR432056. LC and VH were supported by NASA grant #NNX12AI67G and NOAA grant #NA10OAR432056. This work was carried out in the frame of the SMOS-Ocean CNES/TOSCA project. The study was also supported in France by two grants of LEFE/IMAGO and LEFE/GMMC. A. Sommer is co-founded by CNES and UPMC PhD fellowships.
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/article/10.3389/fmars.2015.00107
Adler, R. F., Gu, G., and Huffman, G. J. (2012). Estimating climatological bias errors for the global precipitation climatology project (GPCP). J. Appl. Meteor. Climatol. 51, 84–99. doi: 10.1175/JAMC-D-11-052.1
Boutin, J., Martin, N., Reverdin, G., Yin, X., and Gaillard, F. (2013). Seas surface freshening inferred from SMOS and Argo salinity: impact of rain. Ocean Sci. 9, 183–192. doi: 10.5194/os-9-183-2013
Busecke, J., Gordon, A. L., Li, Z., Bingham, F. M., and Font, J. (2014). Subtropical surface layer salinity budget and the role of mesoscale turbulence. J. Geophys. Res. Oceans 119, 4124–4140. doi: 10.1002/2013JC009715
Centurioni, L. R., Hormann, V., Chao, Y., Reverdin, G., Font, J., and Lee, D. K. (2015). Sea surface salinity observations with Lagrangian drifters in the tropical North Atlantic during SPURS: Circulation, fluxes, and comparisons with remotely sensed salinity from Aquarius. Oceanography 28, 96–105. doi: 10.5670/oceanog.2015.08
Colbo, K., and Weller, R. A. (2009). Accuracy of the IMET sensor package in the subtropics. J. Atmos. Oceanic Technol. 26, 1867–1890. doi: 10.1175/2009JTECHO667.1
Dai, A., Qian, T., Trenberth, K. E., and Milliman, J. D. (2009). Changes in continental freshwater discharge from 1948 to 2004. J. Clim. 22, 2773–2792. doi: 10.1175/2008JCLI2592.1
Delcroix, T., and Hénin, C. (1991). Seasonal and interannual variations of sea surface salinity in the tropical Pacific Ocean. J. Geophys. Res. 96, 22135–22150. doi: 10.1029/91JC02124
Dohan, K., Kao, H.-Y., and Lagerloef, G. S. E. (2015). The freshwater balance over the North Atlantic SPUS domain from aquarius satellite salinity, OSCAR satellite surface currents, and some simplified approaches. Oceanography 28, 86–95. doi: 10.5670/oceanog.2015.07
Dong, S., Goni, G., and Lumpkin, R. (2015). Mixed-layer salinity budget in the SPURS region on seasonal to interannual time scales. Oceanography 28, 78–85. doi: 10.5670/oceanog.2015.05
Donlon, C. J., Martin, M., Stark, J. D., Roberts-Jones, J., Fiedler, E., and Wimmer, W. (2012). The operational sea surface temperature and sea ice analysis (OSTIA). Rem. Sens. Environ. 116, 140–158. doi: 10.1016/j.rse.2010.10.017
Durack, P. J. (2015). Ocean salinity and the global water cycle. Oceanography 28, 20–31. doi: 10.5670/oceanog.2015.03
Durack, P. J., and Wijffels, S. E. (2010). Fifty-years in Global ocean salinities and their relationship to broad-scale warming. J. Clim. 23, 4342–4362. doi: 10.1175/2010JCLI3377.1
Dussurget, R., Mulet, S., Pujol, M.-J., Sommer, A., Kolodziejczyk, N., Reverdin, G., et al. (2015). Surface current field improvements – Regional altimetry for SPURS. Coriolis Mercator Newslet. 52, 39–44.
Farrar, J. T., Rainville, L., Plueddemann, A. J., Kessler, W. S., Lee, C., Hodges, B. A., et al. (2015). Salinity and temperature balances at the SPURS central mooring during fall and winter. Oceanography 28, 56–65. doi: 10.5670/oceanog.2015.06
Gaillard, F., Autret, E., Thierry, V., Galaup, P., Coatanoan, C., and Loubrieu, T. (2009). Quality control of large Argo data sets. J. Atmos. Oceanic Technol. 26, 337–351. doi: 10.1175/2008JTECHO552.1
Gordon, A. L., and Giulivi, C. F. (2014). Ocean eddy freshwater flux convergence into the North Atlantic subtropics. J. Geophys. Res. Oceans 119, 3327–3335. doi: 10.1002/2013JC009596
Gould, J., Roemmich, D., Wijffels, S., Freeland, H., Ignaszewsky, N., Jianping, X., et al. (2004). Argo profiling floats bring new era of in situ ocean observations. Eos Trans. Am. Geophys. Union. 85, 185–191. doi: 10.1029/2004EO190002
Hasson, A., Delcroix, T., and Boutin, J. (2013). Formation and variability of the South Pacific Surface Salinity maximum in recent decades. J. Geophys. Res. 118, 5109–5116. doi: 10.1002/jgrc.20367
Hernandez, O., Boutin, J., Kolodziejczyk, N., Reverdin, G., Martin, N., Gaillard, F., et al. (2014). SMOS salinity in the subtropical North Atlantic salinity maximum: Part 1. Comparison with Aquarius and in situ salinity. J. Geophys. Res. Oceans 119, 8878–8896. doi: 10.1002/2013JC009610
Huffman, G. J., Adler, R. F., Morrissey, M., Bolvin, D. T., Curtis, S., Joyce, R., et al. (2001). Global precipitation at one-degree daily resolution from multi-satellite observations. J. Hydrometeor. 2, 36–50. doi: 10.1175/1525-7541(2001)002<0036:GPAODD>2.0.CO;2
Kerr, Y. H., Waldteufel, P., Wigneron, J.-P., Delwart, S., Cabot, F., Boutin, J., et al. (2010). The SMOS mission: new tool for monitoring key elements of the global water cycle. Proc. IEEE 98, 666–687. doi: 10.1109/JPROC.2010.2043032
Kolodziejczyk, N., Boutin, J., Hernandez, O., Sommer, A., Reverdin, G., Marchand, S., et al. (2015a). Argo SSS and SMOS SSS combination helps monitoring SSS variability from basin scale to mesoscale. Coriolis Mercator Newslett. 52, 16–21.
Kolodziejczyk, N., and Gaillard, F. (2013). Variability of the heat and salt budget in the subtropical southeastern pacific mixed layer between 2004 and 2010: spice injection mechanism. J. Phys. Oceanogr. 43, 1880–1898. doi: 10.1175/JPO-D-13-04.1
Kolodziejczyk, N., Hernandez, O., Boutin, J., and Reverdin, G. (2015b). SMOS salinity in the subtropical North Atlantic salinity maximum: 2. Two-dimensional horizontal thermohaline variability. J. Geophys. Res. Oceans 120, 972–987. doi: 10.1002/2014JC010103
Kolodziejczyk, N., Reverdin, G., and Lazar, A. (2015c). Interannual variability of the mixed layer winter convection and spice injection in the eastern subtropical North Atlantic. J. Phys. Oceanogr. 45, 504–525. doi: 10.1175/JPO-D-14-0042.1
Lagerloef, G., Schmitt, R. W., Schanze, J., and Kao, H.-Y. (2010). The ocean and the global water cycle. Oceanography 23, 82–93. doi: 10.5670/oceanog.2010.07
Lumpkin, R., and Pazos, M. (2007). "Measuring surface currents with Surface Velocity Program drifters: the instrument, its data, and some recent results," in Lagrangian Analysis and Prediction of Coastal and Ocean Dynamics, eds A. Griffa, A. D. Kirwan Jr., A. J. Mariano, T. Özgökmen, and H. Thomas Rossby (New York, NY: Cambridge University Press), 39–67.
Madec, G. the NEMO team (2014). "NEMO Ocean Engine." Note du Pôle de Modélisation. Paris: Institut Pierre-Simon Laplace.
Moisan, J. R., and Niiler, P. P. (1998). The seasonal heat budget of the North Pacific: net heat flux and heat storage rates (1950–1990). J. Phys. Oceanogr. 28, 401–421.
Morel, A., and Antoine, D. (1994). Heating rate within the upper ocean in relation to its bio-optical state. J. Phys. Oceanogr. 24, 1652–1665.
Qu, T., Gao, S., and Fukumori, I. (2011). What governs the North Atlantic salinity maximum in a global GCM? Geophys. Res. Lett. 38:7. doi: 10.1029/2011GL046757
Reverdin, G., Boutin, J., Lorenco, A., Blouch, P., Rolland, J., Niiler, P. P., et al. (2007). Surface salinity measurements – COSMOS 2005 experiment in the bay of biscay. J. Atmos. Oceanic Technol. 24, 1643–1654. doi: 10.1175/JTECH2079.1
Reverdin, G., Morisset, S., Marié, L., Bourras, D., Sutherland, G., Ward, B., et al. (2015). Surface salinity in the North Atlantic subtropical gyre during the STRASSE/SPURS summer 2012 cruise. Oceanography 28, 114–123. doi: 10.5670/oceanog.2015.09
Reynolds, R. W., and Chelton, D. B. (2010). Comparisons of daily sea surface temperature analyses for 2007–08. J. Clim. 23, 3545–3562. doi: 10.1175/2010JCLI3294.1
Schmitt, R. W. (1995). The ocean component of the global water cycle. Rev. Geophys. 33, 1395–1409. doi: 10.1029/95RG00184
Shcherbina, A. Y., D'Asaro, E. A., Riser, S. C., and Kessler, W. S. (2015). Variability and interleaving of upper-ocean water masses surrounding the North Atlantic salinity maximum. Oceanography 28, 106–113. doi: 10.5670/oceanog.2015.12
Skliris, N., Marsh, R., Josey, S. A., Good, S. A., Liu, C., and Allan, R. P. (2014). Salinity change in the World Ocean since 1950 in relation to changing surface freshwater fluxes. Clim. Dyn. 43, 709–736. doi: 10.1007/s00382-014-2131-7
Sweeney, C., Gnanadesikan, A., Griffies, S. M., Harrison, M. J., Rosati, A. J., and Samuel, B. L. (2005). Impacts of shortwave penetration depth on large-scale ocean circulation and heat transport. J. Phys. Oceanogr. 35, 1103–1119. doi: 10.1175/JPO2740.1
Talley, L. D. (2002). Salinity Patterns in the Ocean. Vol. 1. The Earth System: Physical and Chemical. Chichester: John Wiley & Sons, Ltd.
Terray, L., Corre, L., Cravatte, S., Delcroix, T., Reverdin, G., and Ribes, A. (2012). Near-surface salinity as nature's rain gauge to detect human influence on the tropical water cycle. J. Clim. 25, 958–977. doi: 10.1175/JCLI-D-10-05025.1
Trenberth, K. E., Smith, L., Qian, T., Dai, A., and Fassullo, J. (2007). Estimates of the global water budget and its annual cycle using observational and model data. J. Hydrometeor. 8, 758–769. doi: 10.1175/JHM600.1
Yu, L. (2011). A global relationship between the ocean water cycle and near-surface salinity. J. Geophys. Res. Oceans 116:, C10025. doi: 10.1029/2010JC006937
Yu, L., Jin, X., and Weller, R. A. (2008). "Multidecade Global Flux Datasets from the Objectively Analyzed Air-sea Fluxes (OAFlux) Project: Latent and sensible heat fluxes, ocean evaporation, and related surface meteorological variables," in Woods Hole Oceanographic Institution, OAFlux Project Technical Report. OA-2008-01 (Woods Hole, MA), 64.
Keywords: salinity, temperature, budget, meso-scale, advection, SMOS, SPURS
Citation: Sommer A, Reverdin G, Kolodziejczyk N and Boutin J (2015) Sea Surface Salinity and Temperature Budgets in the North Atlantic Subtropical Gyre during SPURS Experiment: August 2012-August 2013. Front. Mar. Sci. 2:107. doi: 10.3389/fmars.2015.00107
Received: 24 September 2015; Accepted: 20 November 2015;
Published: 08 December 2015.
Chris Bowler, École Normale Supérieure, France
Fabien Roquet, Stockholm University, Sweden
Shinya Kouketsu, Japan Agency for Marine-Earth Science and Technology, Japan
Copyright © 2015 Sommer, Reverdin, Kolodziejczyk and Boutin. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Anna Sommer, anna.sommer@locean-ipsl.upmc.fr;
Gilles Reverdin, reve@locean-ipsl.upmc.fr


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text:
Pillars of Eternity: Josh Sawyer talks mods, PC-first focus, Big Head mode, and more
By Hayden Dingman
Games Reporter, PCWorld |
Pillars of Eternity is about a month away from release, so with the game mostly finished I got the chance to sit down for one last, lengthy chat with Obsidian's Josh Sawyer to talk expansion plans, sequel rumors, why PCs are amazing, fast/slow mode, Big Head Mode, Gothic castles, and why Might affects the damage inflicted by a pistol.
All that and more, below.
Side note: While Sawyer talked, Obsidian's Nick Carver was playing through some optional sections of the game for us, so if you see any references to "that hero" or the like, just assume it's Sawyer referencing whatever was on the screen at the time. Also, I have no idea what the official spelling is for some of these areas and characters. I guessed. Sue me.
Josh Sawyer, Obsidian (JS): One of the areas we're showing right now is Radric's Hold. Radric's Hold is encountered within the first couple of hours of the game. You can tackle it immediately. You can wait and come back. There's no level-scaling or anything so you can do it in whatever order you want.
It was important for us to have these grand-scope, very cool 2D environments. This is a Gothic Castle. One of our designers was like "Can we please just have one Gothic Castle?" so we decided to make Radric's Hold. It is actually a dungeon. You can use some diplomacy as you go through it. You can use stealth. You can use your skills in different ways. First, though, we're going to try and just barge our way in, which is one way you can do it.
It is a real-time with pause combat system, so at any time you can pause the game. You also have a lot of auto-pause options. A lot of players prefer to have things set up ahead of time so if a character goes down, something happens, it'll pause right away so they can give new orders.
Fast Mode and Slow Mode
JS: In a big battle like this where there are a ton of combatants you can also go into a "Slow Mode." Slow Mode doesn't run at half speed, it runs at 2/3 speed. It's just enough to bring the speed down so things become a little bit easier to follow, a bit easier to manage. You don't have to quite micro and pause so much.
Not only do you have a slow mode for combat, but you have a fast mode that's good for exploring quickly—usually re-traversal. Exploration is a big part of the game but re-traversal is also a big part of the game that's not necessarily super-enjoyable. Fast mode helps you book it through there.
The final word on classes
JS: There are 11 different classes. This is all part of the Kickstarter campaign. They all play very differently.
We did design the game so you don't have to have a nuclear party. You don't need to have a fighter, a rogue, a wizard and a priest if you don't want to. You can make gimmick parties, you can make a party that's all paladins or all rogues and wizards. Whatever you want. It is designed so the game will be viable and completable no matter how you built your party.
This party that we have right here—all of these characters are companions except this one, which is the main. She's a rogue. There's a fighter. That's Khana, a chanter or bard. That's Durance, the guy who looks like an insane Rasputin. He's a priest. That's Aloth, who is a wizard. And the last one is the Grieving Mother, who is a Cipher. In this case we do have a nuclear party. The way we set up our companions is to cover a wide set of classes. If you just sort of go with inertia you will end up with a nuclear party. But even so, we didn't want to design the game in a way where you required that.
If you don't like these guys, you don't have to take them. In fact, you can even make your own additional characters that are just Adventurers and add them to your party. You can also play solo if you want, although that's incredibly hard.
You'll notice every character [Nick] is playing has some active-use abilities. We did try to make sure that if you wanted to make a character that's very active, even one that's traditionally fairly passive like a fighter, you did have lots of active-use abilities.
However it can be a lot to manage six characters like that, so you can also build characters that are almost fully passive. You don't really have to manage them a whole lot. You can plant them in a location, say "defend that" and they work pretty much fine like that.
FIghters are probably the most passive in terms of how you can build them. You can build up their defensive abilities so they lock people down when they come near, you get a lot of defensive bonuses, they regenerate damage over time, and they have a consistent progression of damage. So if you want them to stand in a location, not die, and do consistent damage? They're great.
You can also build them to be very active though where they're doing crowd control, they're knocking guys away, things like that.
There's nothing I would say "Don't play this if you're a beginner" because when you start out you're only managing your own, single character. I think we progress in a way where it's pretty easy to manage. But I will say that rogues and monks tend to be, of the melee classes, much more active. And especially rogues are much more fragile, and can get screwed up very fast.
On stats
JS: We really put a lot of effort into our stat spread. We've tweaked and tweaked and retweaked this over time. For instance, the Might score increases damage and healing for everything. You might say, "Dude, why should Might affect the damage of my pistol?" and I say, "Shut the $#&^#& up." The point is that it's good for any class that wants to focus on that.
Intellect increases the area of effect and duration of any ability you use. You don't need to be a wizard or anything like that.
It's not a perfect 1-to-1 where you can build whatever you want and there's no trade-off, but if you want to build an idiot muscle-wizard, which is very important to me, you can. If you want to build a brilliant fighter, that's also a very viable character. If you have an idea for a cool character we don't want to say "No, that's unrealistic." We want to say "What's a way we can support that and make it fun?"
We only have five non-combat skills in the game. We did that because we wanted to make sure each skill got a lot of use, regardless of who had the skill. Aloth is very focused in Lore. Lore is great in conversations for your main character but it's also what's used for reading scrolls. Yes, you can make a fighter that just reads scrolls all day long. It's not a restricted skill. Nothing is a restricted skill. You do not need to have a rogue if you want to disarm traps or be stealthy. They're better at it! But it's not a requirement.
Let's say you wind up with six characters that have the Mechanics skill jacked up. Because you're &%^#%ing crazy. You jack them all up. Every character can plant one trap at a time, and the Mechanics skill will increase the accuracy and the power of that trap. So if you want to make the trap-laying party? You can jack everyone's Mechanics and go out and place all that.
If you jack everyone's Lore skill, they can all use scrolls. If you jack everyone's Survival skills, all potions will last longer and all food items will last longer. We tried to make sure every skill has some usefulness if you have some overlap or redundancy. It's frustrating to build a character and then someone joins the party that has the same skillset and you're like "Well, thanks dude. That's useless."
On friendly fire
JS: (To Carver) Show one of Aloth's AOEs. You can see there are two radii for that. The inner circle is completely friend-or-foe. Everyone will be hit [by the spell]. That border area? That's a bonus from his intellect, and that area is foe-only.
So you can throw a fireball and if something falls in that outer ring, if it's an ally they won't be hurt. That's a way we allow those spells to scale without, "This gets bigger but my party gets hurt more easily."
On guards
JS: Guards will call for help. They won't run away but they will call for help. And you do have to be careful about where you choose to engage them. You can actually take on individual guards by themselves, but there are patrollers so you might have adds, and when you have those adds they might shout and pull guys from behind them. You kind of have to watch.
We tried to make sure every map did have some patrollers on it because even a few of them can really change the dynamics of how fights play out.
Read on to page two for more information on expansions, tabletop Pillars of Eternity, Big Head Mode, and more.

redpajama_set_name: RedPajamaCommonCrawl


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Matija Greguric (born 17 September 1996) is a Croatian male hammer thrower, who won an individual gold medal at the Youth World Championships.

References

External links

1996 births
Living people
Croatian male hammer throwers

redpajama_set_name: RedPajamaWikipedia


Have you been curious on how restaurants began? Or how its birth brought a major impact on anyone's lives? Restaurants have been around in some form for most of the human civilization, the evolution of this type of business brought a revolutionary effect on the family, industrialization and in the economics at a global level.
Back in the days, people who established permanent homes usually make their own food: farming and domesticating animals. When people became knowledgeable and skilled to earn a living, it became inevitable for them to designate the home-based preparation of food to an individual or enterprise. Restaurants were born with that need to simply save a lot of time and to escape the tedious routine of preparing meals all day. Instead of the staple meals we commonly eat, we can now go for a certain food we desire presented in the menu. Also, we can now purchase continental food and have it delivered at our homes.
Numerous food varieties came out with the increase of people going into this line of business. Hamburgers, doughnuts, and even the brewed coffee drink cause the growth of restaurant chains especially in Singapore making it a multi-billion business worldwide. Restaurants changed not just the economic structure of the world but also the lifestyle of people generally. Today, a lot of working people rarely cook at home and simply purchase food outside. Some families on weekends go on food trips to neighboring and foreign cities for gustatory adventures.
However, restaurants particularly fast food outlets brought adverse effect in people's health. These commercial food establishments cater unhealthy foods just to make money. But with the continuous growth of wellness and fitness industry, more and more restaurants now offer fresh, healthy and delicious options from their menu. This proves that restaurants will certainly stay to provide support to every individuals crave for good and delicious food at any time of the day.
The highly skilled professionals of Bacall Conniff Business Advisors will give entrepreneurs an excellent accounting and financial service to help the restaurant industry strive in the global economy.
Copyright© Rad Arnold. all right reserved.


Saturniid Moth Cocoon Set is rated 4.7 out of 5 by 7.
Six identified cocoons (3 each of 2 species) of large saturniids. With instructions. Note: Available October through May.
Six identified cocoons (3 each of 2 species) of large saturniids. With instructions. Note: Available October through May. Restricted in some states. Substitutions will be made if possible.
Rated 5 out of 5 by the krol krew from Excellent customer service! Wonderful moths! We love insects and we love these moths! After we bought this product, two moths hatched fine, but three were already dead. Carolina then sent us six replacements instead of the three we requested (thanks guys!). All of these cocoons were alive and they all hatched but currently we are still waiting for the last one. Though it takes a lot of patience, these moths are incredibly interesting and beautiful, and we feel that it was worth it. We understand that shipping these moths and being able to tell whether they are dead or alive is hard, so we do not feel that the dead moths were the result of poor service. Great product and we will be coming back!
Rated 5 out of 5 by bugmom4 from great specimens, great customer service this is a neat collection or set. we got it for whole family, mainly son who does entomology and loves moths. have had all but two emerge, and one die while emerging, while sad, we understand that this does happen- BUT, called customer service and they send replacement like their site says, great to work with! will come back!
Rated 5 out of 5 by Brittany from Interesting and educational I ordered this set last month. 2 Luna moths (1 male, 1 female) emerged after approximately 2 weeks. Last week, a cynthia moth and male promethea moth emerged.Yesterday another cynthia moth emerged. Just waiting on one more cocoon, I hope it makes it! It is a promethea and we are hoping for a female.
Rated 4 out of 5 by Jacob9 from Fantastic, but results still pending I would give this product 5 stars, but at the moment (2.5 weeks in my care) only 2 of the 6 moths have hatched. I remain hopeful that the others are on the way, but I am a bit concerned that they won't hatch. The two that hatched were a Cynthia moth and a Luna moth and they are absolutely wonderful to observe. The remaining cocoons house 1 Cynthia moth, 1 Luna moth, and 2 Promethea moths. Overall an excellent product, but I am still waiting to see if the hefty price tag is worth it.
Rated 5 out of 5 by Tuley2017 from So Fascinating! We received our moth cocoons a few weeks ago and late last week our first moth "hatched", a handsome male Polyphemus Moth. Everyone got out their cameras and cellphones to take photos of it. It was a great educational moment for everyone as we were able to explain how the moths develop, what the bushiness of the antennae indicates, what the transparent "holes" in the wings were, how the moths reproduce, what their lifespans were, etc.. We're anxiously awaiting to see what the other moths look like when they emerge.
Rated 5 out of 5 by MrBirdman from Great Experience We purchased 6 Saturniid cocoons for my daughter to observe. She had hoped for a mix of species. They all ended up Polyphemus but she was very happy as all 6 hatched and were beautiful. It was a very rewarding experience for her. I had raised Polyphemus as a child so this was fun for me as well.
Rated 4 out of 5 by Kinderbug from Saturnid moths Unfortunately one of the luna moths emerged in transit. The other one came out and was beautiful. The Cynthia and Promethea moths have not emerged yet.


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Home / bulgaria / Lightyear One – a sunny family car that we probably will not buy
Lightyear One – a sunny family car that we probably will not buy
bulgaria June 26, 2019 bulgaria
The problem with solar cars is that a large set of batteries and solar cells adds too much weight to the chassis, which makes solar technology ineffective when driving a ton of iron.
It seems, however, that Lightyear has managed to find the right balance and put it in the Lightyear One prototype – a family solar vehicle that can travel up to 725 kilometers per charge.
The entire upper part of the car is covered with super efficient solar cells, which add a sufficient load to cover 12 kilometers per hour.
Source: Lightyear
The car is extremely spacious and has a total of 780 liters of luggage space, which makes it the right choice for people with children.
The model is powered by four engines, the power of which is adapted to the method of solar charging and the ecological profile of the car.
Lightyear You can accelerate from 0 to 100 km / h in about 10 seconds, which is quite small compared to the power of the Tesla models, but it is enough to overtake us.
According to the company's calculations, the vehicle will consist of about 40% of the solar load in normal daily use, and the remaining 60% will have to be powered by a central power source.
Everything around the car sounds great, except for its price. Lightyear One will be available on the market in 2021 and will cost up to 150,000 euros, which means that it will not likely become a mass model.
Are solar roads effective?
Flight without wings
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Lina presented the Femoflor screen for women's health
They closed the port of Varna: Long-term fraud – Bulgaria
Albania has banned television broadcasting songs Ceca Velichkovic
Ilon Musk develops new, advanced technology
Ludogorets takes a historical pot against Ferencvaros
Borisow for a detained hacker: Such IT wizards must work for the state


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Evergrande to restructure all offshore public bonds amid debt crisis
TheBL staff 12/10/21, 06:35
Evergrande to restructure all offshore public bonds amid debt crisis, on Oct. 6, 2021. (Việt Hoàng/FLICKR)
According to Sound of Hope, China's debt-laden Evergrande property group plans to restructure its offshore public bonds and private debt. The change was China's most remarkable asset restructuring of all time.
Evergrande announced that it had encountered difficulties paying a $260 million guaranteed offshore bond on Dec. 3. The company still has about $19.2 billion in outstanding offshore public bonds and $8.4 billion in local notes.
According to the documents submitted by Evergrande to the Hong Kong Stock Exchange, the company's board of directors established a risk management committee with five members from outside the company after the Guangdong Province government announced they had sent a group to deal with the company's problems.
A source revealed that Evergrande included all debts in the restructuring process. The movement was considered an act to calm the market. The source admitted the restructuring process has yet to start, and plans could be changed.
Evergrande's restructure announcement has led to its market value fall historically by 20% in Hong Kong stocks at the beginning of this week. At the same time, its U.S. dollar bonds also recorded the most significant decline in history.
Ren Shuili, a Bloomberg Opinion columnist covering Asian markets, warned the Chinese real estate developers that if they tried to pay the debt, they might face negative economic consequences.
Evergrande's contract sales fell by 93% year-on-year in November. Real estate developers like Fantasia had to file for liquidation after defaulting in October, which meant that companies with debt problems were on the verge of danger.
Evergrande founder sells Hollywood Hills mansion at loss
Evergrande defaulted on $260 million debt: Bankruptcy could be next
China Evergrande failed $260 million of a debt obligation
Evergrande founder sells almost 10% stake amid debt crunch
Tags:Evergrande debt crisis China Evergrande founder Hui Ka Yan
Largest artificial island development in China is ordered demolished
China's Evergrande seeks onshore bond payment delay
Evergrande shares halted as China orders demolition of 39 housing projects
Evergrande forced to demolish 39 housing projects in 10 days


Unspeakable Axe Records hailing from Athens, Georgia got its start in 2013 as a sub label of Dark Descent Records. Their primary focus are bands with a more thrash oriented sound than its parent label but there's still plenty of death metal and crossover on their roster. Every release is a pure homage to its respective genre. No experimentation, no avant garde, just pure unapologetic wear your influences on your sleeve like a red badge of courage metal. On that note, here's 3 of their recent releases for you to check out.
Existing in one form or another since 1985, bay area death/thrash act, Insanity, return with original vocalist/guitarist, Dave Gorsuch leading the charge. Since their debut album in 1994, Death After Death, they've released 3 compilations, a demo and an EP. Now 21 years later and they have their sophomore full length, Visions of Apocalypse. It's cliche to say a band has an old school sound/feel/production, but this album sounds like it was written and recorded in the late 80's and just finally released. Yeah, yeah, yeah, I know what you're thinking, so give it a listen and see if I'm wrong.
Scorched, from Delaware, serve up some meat-n-potatoes 1990's death metal on their debut self titled demo. I'm not really sure why they're calling this a demo since the production is perfectly acceptable for an EP. Normally, back in the day a demo was 2-3 songs, but here they give you 6 tracks over 17 minutes. There's nothing original going on here yet they don't really sound like any one particular band. It's like they took everything about 1990's death metal and threw it into a blender and the cohesive elements rose to the surface.


In any building or community there are many pollutants that could cause significant health risks and/or property damage if not handled or stored properly.
In older buildings you have to worry about exposures like lead, asbestos, or leaky oil tanks for your boiler. For multiple building communities, you may have the same exposures but also be storing pool chemicals on the premises.
There are many other hazardous pollutants that could cause issues, but the main one in homes and community associations is typically leaking from a fuel tank. Depending on your insurance policies, you may or may not have coverage in the event of a lawsuit, or for remediation.
Environmental Impairment Liability, also referred to as Pollution Liability, provides coverage for negligence or omission resulting in pollution or environmental contamination. Depending on a number of factors, such as size of your building, or the age of the any fuel tanks, environmental coverage can be relatively inexpensive, especially when you consider the cost of having to clean up a pollution related mess or the cost to defend a suit lodged by an injured party.
When oil leaks from a covered fuel tank into the ground, it can result in very expensive clean up fees, especially if it gets into nearby water. We are talking easily hundreds of thousands of dollars. Coverage is especially important if you have an underground fuel tank, as many insurance carriers believe that it is a matter of when they will leak, not if they will leak.
When it comes to the environment, issues can arise gradually or out of nowhere. It's important to make sure you're as ready and protected as you can be. Please contact us for more information.


OEEsystems Best In Class, Smart Factory, Performance Management software is trusted by thousands of users in hundreds of sites from Seattle to Shanghai, to deliver sustainable OEE improvements. It has been designed to provide OEE Analysis and Reporting for DISCRETE, BULK and CONTINUOUS MANUFACTURING processes. Visibility, control or process improvement, whatever your motivation, our OEE Software Trial facility helps you get started on your OEE project and delivering results fast.
Pros: user interface is easy to use, there is a lot of reports.
support team is fast. Good knowledge of OEE.


I created this to be reduced in size from the original by .75 to reduce print time, use less desiccant and just be physically smaller. I added a center chamber to increase airflow through the desiccant and again reduce the desiccant used. I also added more holes. Laid both the lid and the box out on the build platform together and printed great. The lid fits perfect with no cleanup needed.
Added a chamfer to the bottom of the support ribs that support the top of the center column for easier printing.
Also Added a though hole version (OpenE) for better air circulation and to allow airflow if stacking multiple boxes on top of each other. Fill to even with top of inner supports then the lid should seal the inner and outside. Do not fill above the top of the inner rib supports.
Used PLA Plus material on a Monoprice maker select plus with glass heat bed. Print head was 210 degrees and bed was 50. Placed both the lid and the box on the build platform together and printed great. The lid fits perfect with no cleanup needed.


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HomeBig Dick XXX Webcam Chat RoomsAnalysis in bisexuality is regarded as by many...
Analysis in bisexuality is regarded as by many people become inefficient or inadequate.
Bisexuality happens to be understood to be the proclivity to behave or even to undertake actions which can be intimate in the wild with both male and partners that are female.
different theories when it comes to origins and degree of bisexuality occur, particularly in reference to the prevalence of pure homosexuality and heterosexuality. Nonetheless, the idea of bisexuality has additionally been used generally speaking to your idea of a scale, described as the intimate orientation continuum, which steps the level to what type is inclined toward heterosexual task or activity that is homosexual.
Throughout history, bisexuality is relegated to views that are extreme. This has either been commonly accepted since the standard or template kind of sex for people, or it's been refused as being a social theory or assumption that may explain a person's intimate recognition. Modern debates concerning the origins of intimate orientation or sexual identification are mirrored likewise into the topic of bisexuality. There are numerous of theorists whom genuinely believe that hereditary facets could be at the job, other individuals who think the environmental surroundings gets the influence that is strongest yet others whom stress the part of hormones in intimate behavior.
Numerous communities, especially conservative, spiritual people, help heterosexuality since the norm. This could manifest either socially or according to clinical theory.
Socially, it is often related to governmental and movements that are social discriminate against those who cannot considering by themselves become homosexual. Other people get in terms of to think it really is an expansion of social or governmental impacts that seek to distribute the practice of non behavior that is heterosexual. Another view is the fact that bisexuality exists as being a transitional mindset for homosexual people who need to conceal their homosexuality or try not to yet understand they've been solely drawn to similar intercourse, or whom will not drop their heterosexual "identity" as a result of social prejudice. Both streams of idea rebuff numerous scientific studies that have actually led determined that sex just isn't consistent or exclusive.
Based on the United states Psychiatric Association, "to date there aren't any replicated systematic studies supporting any particular biological etiology for homosexuality. Likewise, no particular psychosocial or household powerful cause of homosexuality was identified, including records of childhood intimate abuse." This declaration would indicate that most of the debate in regards to the origins of bisexuality is based on social, social and political sensitiveness, whereas in reality, there is absolutely no conclusive proof that bisexuality is developed away from a mainly or entirely biological supply, or perhaps a mainly or entirely ecological supply. A genetic or biological phenomenon, many activists in the lesbian/gay/bisexual/transsexual community have shied away from this point, fearing that should future research identify biological influence, it could lead to genetic screening or prenatal testing and mass abortions while socially, it has become common to consider homosexuality or bisexuality.
Sigmund Freud and Alfred Kinsey will be the most well-known advocates for either a form that is base of or a continuum of intimate choice. Freud assumed that bisexuality had been the default and therefore attraction to, or sexual intercourse with one or even the other, sex could be latent later on in big dick webcam life as the other manifested itself. Kinsey included the continuum when you look at the analysis of these whom he interviewed during their studies on intercourse. Research reports have shown bisexuals to become more intimately active also to take part in more fantasy that is sexual heterosexuals or homosexuals. Their task is often more intense; as an example, feminine bisexuals have now been discovered to possess more intense sexual climaxes an average of than ladies along with other orientations that are sexual.
Analysis in bisexuality is known as by numerous become inadequate or ineffective. Numerous fee that the scientific studies are commonly done in tandem with research on homosexuality, which may discount the theories and their derivatives frequent among the kind of Freud and Kinsey. Additionally, research focusing exclusively on bisexuality is sporadic and scant.


We offer training for both horse and rider, and can travel to your premises to carry out training. If a few people at the same barn would like training, the trip charge is split between all clients.
A basic outline of our pricing structure is outlined below, however if necessary I can work up a detailed price quotation (for example a 'package' price to start, back and 'ride away' a young horse).
For young children (under six years old) I recommend a thirty minute lesson, as their concentration and muscle tone doesn't lend itself to longer sessions. A thirty minute lesson is $30 (or $100 for a block of 4), and while the child may be required to do a very small amount of light grooming, the majority of the time will be spent on horseback, whether riding or 'playing' (working on confidence and balance through various exercises while the horse is halted).
We now offer local horse hauling, in a 2 horse straight load trailer (up to 16hands) which has been fully serviced and professionally checked out in the last few months. Hauling is available to shows or between barns (does not have to be a horse coming to our barn). Please contact us for more details.


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Imagination Announces Vulkan API, New Graphics API for PowerVR Rogue GPUs
By Nick Sutrich March 03, 2015, 8:40am
Today at Mobile World Congress 2015 Imagination, the creator's behind the PowerVR lineup of graphics processors (GPU), have announced a brand new API designed by the Khronos group, specifically for mobile devices and PowerVR chipsets in mind. Imagination has been testing the Krhonos group's new API Vulkan on PowerVR Rogue GPUs and it promises to deliver considerable improvements in 3D rendering performance all while reducing CPU overhead and workload. This idea is very similar to what AMD announced with its Mantle API, and Microsoft followed suit later with the announcement of Direct X 12 and its Direct3D 12 API. All of these APIs have one big thing in common: programming for the GPU at the hardware level and lightening the load on the CPU so that it's free to do other tasks.
Imagination and Khronos are gearing this new API up to replace OpenGL ES 3.0, which it says is a limited API due to its high CPU overhead. High CPU usage while rendering graphics not only takes the CPU away from other important tasks like multi-tasking and other background processes but also drains the battery quicker. GPUs on the other hand have become increasingly more powerful when it comes to computational power, and with the advent of compute shaders we've seen the shift from CPUs being used for tasks like physics and other intensive processing methods to GPUs taking all the workload. As GPUs are made for very specific types of computational tasks and CPUs are only made for general processing tasks, offloading this type of processing to the GPU makes plenty of sense.
With Vulkan developers can take advantage of the low-level API Imagination is providing by letting their applications do all the high-level management work while the driver handles all the low-level tasks. This results in slightly more complex application code but keeps developers from having to work around the driver as they have for things like shader pre-warmings in OpenGL ES. Vulkan also provides more consistent performance than OpenGL ES because it's designed specifically for PowerVR GPUs and thus has very specific code to write for, unlike OpenGL ES where generic code may run differently on various platforms. If you're interested in reading up more on the new API including specifics check out the Imagination blog post at the source link below, and check out our hands on video of the new Vulkan API.
March 03, 2015, 8:40am
Source: Imagination Blog
Android NewsMobile World Congress NewsVR News
Nick Sutrich
Nick has written for Androidheadlines since 2013, is Reviewer for the site, and has traveled to many tech events across the world. His background is as Systems Administrator and overall technology enthusiast. Nick loves to review all kind of different devices but specializes in Android smartphones, smartphone camera reviews, and all things VR, both here on the site and on our YouTube channel. He is very passionate about smartphones and the continued improvement they can bring into people's lives and is an expert on many different types of technologies, including mobile devices, VR, and cameras. Contact him at [email protected]