Inter‐annual variability of summer monsoon rainfall over Myanmar

Abstract

Rainfall over Myanmar has large inter‐annual variability causing droughts and floods in many years. In this study, rainfall variability (in monthly scale) over Myanmar during summer monsoon has been examined using observed data. It is found that monthly rainfall in June, July and August months do not have any relation among each other, indicating that monthly rainfall received in Myanmar in these 3 months vary due to different mechanisms. In order to develop an effective drought monitoring and prediction system for the country, such mechanisms of rainfall variability have to be studied. Using composite wind analysis for excess and deficit rainfall years, it is found that deficiency of rainfall occurs when south‐westerly winds at 850 hPa are weaker over the region in June. During excess rainfall years, south‐westerly wind anomalies seen in June turn to stronger and milder westerly winds in July and August, respectively. However, a cyclonic anomaly is seen over North Bay of Bengal adjoining western coast of Myanmar in all the 3 months. It is found that the Myanmar rainfall is correlated positively with the sea surface temperature over central Pacific Ocean. An empirical orthogonal function (EOF) analysis of monthly and seasonal mean rainfall over the region has been carried out. The leading mode (EOF‐1) shows coherent spatial patterns between the Indian monsoon rainfall over east and central parts of the India and rainfall over the western Pacific. The second leading mode of seasonal rainfall shows a trend in rainfall during the study period.

Assessment of GPM and TRMM Multi-Satellite Precipitation Products in Streamflow Simulations in a Data-Sparse Mountainous Watershed in Myanmar

“…The downstream area of the basin is located in the central dry zone of Myanmar, which is the country's major agricultural region. Owing to less rainfall and higher air temperature, the downstream region is facing frequent droughts, and severe and extreme droughts hit the region in 1997-1998, 2001, 2005, 2008-2009, and 2012-2014 [46]. Severe flood and drought disasters threaten property, human lives, food security and ecological biodiversity in the basin, making it important and urgent to assess flood/drought risks and adopt effective control measures.…”

Evaluation of spatio‐temporal rainfall variability and performance of a stochastic rainfall model in Bangladesh

“…() used Tropical Rainfall Measuring Mission (TRMM) estimations to assess the spatio‐temporal variabilities over Africa continent. Similarly, in India and Myanmar, the neighbouring countries of Bangladesh along the Bay of Bengal, the variabilities of monsoonal rainfall were also widely investigated (Sadhukhan et al, ; Mohapatra et al, ; Shrivastava et al, ; Thomas and Prasannakumar, ; Chaudhary et al, ).…”

Time‐lagged correlations associated with interannual variations of pre‐monsoon and post‐monsoon precipitation in Myanmar and the Indochina Peninsula

“…The La Niña‐like pattern of simultaneous relationship between SST and precipitation in the region shown in Figures (bottom left) was already reported in several studies (e.g., Buckley et al ., ; Ummenhofer et al ., ; Shrivastava et al ., ). In addition, the current study shows the evolution of significant regression coefficient of SST upon the PC1 of EOF analysis on the pre‐monsoon precipitation over the large domain in terms of time lags up to 12 months ahead.…”