Global cloud height fluctuations measured by MISR on Terra from 2000 to 2010

Abstract

Self-consistent stereo measurements by the Multiangle Imaging SpectroRadiometer (MISR) on the Terra satellite yield a decrease in global effective cloud height over the decade from March 2000 to February 2010. The linear trend is-44 ± 22 m/decade and the interannual annual difference is-31 ± 11 m between the first and last years of the decade. The annual mean height is measured with a sampling error of 8m, which is less than the observed interannual fluctuation in global cloud height for most years. A maximum departure from the 10-year mean, of-80 ± 8 m, is observed towards the end of 2007. These height anomalies correlate well with the changes in the Southern Oscillation Index, with the effective height increasing over Indonesia and decreasing over the Central Pacific during the La Nia phase of the oscillation. After examining the net influence of Central Pacific/Indonesia heights on the global mean anomaly, we conclude that the integrated effects from outside these regions dominate the global mean height anomalies, confirming the existence of significant teleconnections. Copyright 2012 by the American Geophysical Union.