A multi-sensor climatological view of double ITCZs over the Indian Ocean |
| |
Authors: | Madathiparambil Ranganathapai Ramesh kumar Abhay Devasthale Gad Levy Syam Sankar Stephan Bakan Hartmut Grassl |
| |
Affiliation: | 1. National Institute of Oceanography , Dona Paula, Goa, 403004, India kramesh@nio.org;3. Swedish Meteorological and Hydrological Institute , 60176, Norrk?ping, Sweden;4. NorthWest Research Associates , Seattle, WA, 98052, USA;5. National Institute of Oceanography , Dona Paula, Goa, 403004, India;6. Max Planck Institute for Meteorology , Hamburg, D-20145, Germany;7. Meteorological Institute, University of Hamburg , Hamburg, D-20145, Germany |
| |
Abstract: | We characterize the climatological features of the double inter-tropical convergence zones (DITCZs) over the western Indian Ocean during November–December by a synergistic analysis of the Hamburg Ocean Atmosphere Parameters and Fluxes from Satellite (HOAPS III) data (1988–2005) and the National Aeronautics and Space Administration's (NASA's) A-Train data (2002–2009). We investigate rainfall, freshwater flux and cloud liquid water, cloud fraction and relative humidity over the DITCZs. In addition, the daily rainfall data from the Global Precipitation Climatology Project (GPCP) are used to document the DITCZs during the El Niño southern oscillation (ENSO) events. An analysis of the GPCP data shows that the DITCZs are clearly discernible during strong ENSO events (1997, 2002 and 2006), in sharp contrast to the DITCZs in the eastern Pacific Ocean, where they are absent during ENSOs. Further, these convergence zones on either side of the equator are of short duration, approximately 3–6 pentads during November and December. All satellite sensor data sets consistently capture the major features of DITCZs. As an accurate simulation of DITCZs in coupled global climate models remains a challenge, the results from the present study would provide a platform for evaluating these models. |
| |
Keywords: | |
|
|