coverage is moored measure VS. By global 2000: ~2,200 drifting and 915 moored. Merchant PS ±0.5 mb assumed 3 main varies About 7,400 ships ≥ TS ±1°C same as for shipping greatly (3500/da) in 1990. By (1) Surface VS ±1.5–3 m/s surface land routes 2000: 777 ships. Few Only rhS ±10% station ships in southern oceans (2) ASAP or T ±1°C assumed 12 main ~50 mb varies About 15 ships (30/da) ≥ other upper air V ±3 m/s same as for shipping greatly equipped by 1989 rh ±10% radiosondes routes Commercial Aircraft: (1) Post-flight V ±6 m/s less error for continuous 200–300 500–1000 (~100 reports per day) reports inertial air routes mb level km roughly 10 observations navigation only per report system (INS)
coverage is global moored measure VS. By 2000: ~2,200 drifting and 915 moored. Merchant (1) Surface Only PS TS VS rhS ±0.5 mb ±1°C ±1.5–3 m/s ±10% assumed same as for surface land station ≥ 3 main shipping routes varies greatly About 7,400 ships (3500/da) in 1990. By 2000: 777 ships. Few ships in southern oceans (2) ASAP or other upper air T V rh ±1°C ±3 m/s ±10% assumed same as for radiosondes ≥ 12 main shipping routes ~50 mb varies greatly About 15 ships (30/da) equipped by 1989 Commercial Aircraft: (1) Post-flight reports V ±6 m/s less error for inertial navigation system (INS) continuous air routes 200–300 mb level only 500–1000 km (~100 reports per day) roughly 10 observations per report
Chapter_2_v4-BW-macro.docx