Abstract
Preliminary studies on ITCZ show that the displacement of this system can play an undeniable role in the climate of tropical regions as well as in surrounding areas. The purpose of this study is to investigate the annual ITCZ movement in the Indian Ocean and East Africa region and to select the appropriate and reliable index for ITCZ positioning. To conduct this research, the ERA-interim reanalysis gridded data from the European Centre for Medium-Range Weather Forecasts (ECMWF) was used to determine the location and spatial displacement of the ITCZ. The results showed that the HCC index is the appropriate index to detect the annual ITCZ displacement in all months of the year. The SH and P indices were in second place in terms of importance and accuracy in identifying the behavior and spatial displacement of the ITCZ system. The TCWV index has been a weak index to detect the ITCZ annual location and displacement. During the three months of winter, the ITCZ bends off the east coast of Africa to the southern latitudes and enters the waters of the Indian Ocean along the northwest-southeast. In the other words, the average ITCZ position on land is about 5˚–6˚ north latitude over the waters of the Indian Ocean. On the contrary, from April to the end of September, in the range of 30˚–50˚ E (Sudan), the ITCZ bends and extends to the northeast. During the summer months, this northward movement sometimes reaches up to 20˚.
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Acknowledgements
We acknowledge the European Centre for Medium-Range Weather Forecasts (ECMWF) for providing the required data for the present study. The ERA-Interim data were obtained via the ECMWF website.
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Lashkari, H., Jafari, M. Annual displacement and appropriate index to determine ITCZ position in East Africa and the Indian Ocean regions. Meteorol Atmos Phys 133, 1111–1126 (2021). https://doi.org/10.1007/s00703-021-00797-y
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DOI: https://doi.org/10.1007/s00703-021-00797-y