The La Nina climate phenomenon is strengthening, increasing the
likelihood an active hurricane season could get even busier. The
update from the National Oceanic and Atmospheric Administration
on Thursday comes as residents of Texas are cleaning up from the
deluge of Tropical Storm Hermine, and Tropical Storm Igor is
drifting in the Atlantic. La Nina is marked by a cooling of the
tropical Pacific Ocean and was reported to be developing a month
ago. It strengthened throughout August and appears likely to
last at least through early 2011, NOAA's Climate Prediction
Service said. "La Nina can contribute to increased Atlantic
hurricane activity by decreasing the vertical wind shear over
the Caribbean Sea and tropical Atlantic Ocean," the center
noted. Wind shear is a sharp difference in wind speed at
different levels in the atmosphere. A strong wind shear reduces
hurricanes by breaking up their ability to rise into the air,
while less shear means they can climb and strengthen. NOAA has
been calling for an above-no