TITLE:
Surface Humidity Changes in Different Temporal Scales
AUTHORS:
Igor Zurbenko, Ming Luo
KEYWORDS:
Specific Humidity Climate, El Niño-Like Movement, Long-Term Trend, KZ Filters, Spatial Pattern, Temporal Scales, High Resolution, Visualization
JOURNAL NAME:
American Journal of Climate Change,
Vol.4 No.3,
June
2,
2015
ABSTRACT: As the
key driven factor of hydrological cycles and global energy transfer processes,
water vapour in the atmosphere is important for observing and understanding
climatic system changes. In this study, we utilized the multi-dimensional
Kolmogorov-Zurbenko filter (KZ filter) to assimilate a near-global
high-resolution (monthly 1°× 1°grid) humidity climate observation database
that provided consistent humidity estimates from 1973 onwards; then we examined
the global humidity movements based on different temporal scales that separated
out according to the average spectral features of specific humidity data.
Humidity climate components were restored with KZ filters to represent the
long-term trends and El Nino-like interannual movements. Movies of thermal maps
based on these two climate components were used to visualize the water vapour
fluctuation patterns over the Earth. Current results suggest that increases in
water vapour are found over a large part of the oceans and the land of Eurasia,
and the most confirmed increasing pattern is over the south part of North
Atlantic and around the India subcontinent; meanwhile, the surface moisture levels
over lands of south hemisphere are becoming less.