Summer precipitation determinant factors of Iran's South-East

Document Type : Scientific and Research

Authors

1 Associate Professor of Climatology, Kharazmi University, Tehran, Iran

2 Ph.D. Candidate in Urban Climatology, Kharazmi University, Tehran, Iran

Abstract

Indian Ocean is known as a source of moisture for southeast of Iran due to summer precipitation. In this study, in order to investigate the role of SST of Indian Ocean, and the convergence and divergence fields in the precipitation of southeast of Iran, precipitation data of five synoptic stations were used during 2000-2010, including Iranshahr, Khash, ChahBahar, Zabul, and Saravan. To investigate synoptic circumstances of precipitation, different atmospheric levels of data was obtained from National Oceanic and Atmospheric of United States (NOAA) website with the horizontal resolution of 5.2 degree. Afterward, maps of wind, heights, and moisture flux were prepared. The results show that these three important factors (including Indian Ocean surface temperature (SST), convergence and divergence fields, and monsoon returned east jet stream) have one important role in the summer rainfall event for the study region. In addition, summer precipitation is influenced by the wet and shallow summer monsoon, sea surface temperatures, and convergence and divergence in continental regions. East jet stream have also been effective in these regions. Summer rainfall patterns. have played roles in this region, including the convergence of the wind in southeast of Iran and the divergence of wind in the southeast of Arabian Peninsula in first pattern. The above circumstances as well as high temperatures of sea surface are considered in second pattern, and high sea surface temperature and the monsoon East jet stream in third pattern.

Keywords

References

Bollasina, M.; Nigam, S. (2009). Indian Ocean sst, evaporation, and precipitation during the South Asian summer monsoon in IPCC-AR4 coupled simulations. Climate Dynamics, 33: 1017–1032. DOI: 10.1007/s00382-008-0477-4.
Byeong, H.; Kyung, J. (2015). Observed changes of global and western Pacific precipitation associated with global warming SST mode and mega ENSO SST mode. Climate Dynamics, 45: 3067-3075. DOI: 10.1007/s00382-015-2524-2.
Chloe, P.H.; Pascal Terray, S.; Bastien, M.; Takeshi, I.; Tomoki, T.; Toshio, Y. (2014). Impacts of Indian Ocean SST biases on the Indian Monsoon as simulated in a global coupled model. Climate Dynamics, 42: 271-290. DOI: 10.1007/s00382-013-1671-6.
Dietmar, D. (2011). An objective analysis of the observed spatial structure of the tropical Indian Ocean SST variability. Climate Dynamics, 36: 2129-2145. DOI: 10.1007/s00382-010-0787-1.
www.esrl.noaa.gov/psd.
Ghyslaine, B.; Pascal, T.; Serbastien, M. (2012). Robustness of SST teleconnections and precursory patterns associated with the Indian summer monsoon. Climate Dynamics, 38: 2143-2165. DOI: 10.1007/s00382-011-1100-7.
He Ji, Y.; Jingjing, U.; ShenXin, Y. (2007). Impacts of SST and SST anomalies on low-frequency oscillation in the tropical atmosphere. Advances in Atmospheric Sciences, 24(3): 377-382. DOI: 10.1007/s00376-007-0377-2.
Hulme, K.; Hulme, M.; Kelly, M. (1993). Exploring the Links between Desertification and Climate Change. Environment, 35: 4-11. DOI: 10.1080/00139157.1993.9929106.
Hung, R.; Hung, P. (2009). Delayed atmospheric temperature -9 response to Enso SST role of high SST and the Western Pacific. Advances in Atmospheric Sciences, 26(2): 343-351. DOI: 10.1007/s00376-009-0343-2.
Jahanbakhsh Asl, S.; Zeinali, D.R.; Banafsheh, M.I.; Babaeian, D.R. (2012). The effect of fluctuations of the Mediterranean Sea surface temperature in rainfall of the western half of Iran. Journal of Geographical Society of Iran, 1: 161-176. [in Persian]
Jasti, S.; Chowdary, A.P.; SayantaniOjha C.G. (2015). Role of upper ocean processes in the seasonal SST evolution over tropical Indian Ocean in climate forecasting system. Climate Dynamics, 45: 2387–2405. DOI: 10.1007/s00382-015-2478-4.
Khosravi, M.; Saligheh, M.; Sabbagh, B. (2011). The impact of sea surface temperature anomalies of the Arabian Sea on rainfall of Iran’s southeastern coasts in Autumn and Winter. Tabriz, Journal of Geography and Planning, 37: 81-59.
Krishnamurthy, L.; Krishnamurthy, V. (2015). Decadal and interannual variability of the Indian Ocean SST. Climate Dynamics, 46: 57-70. DOI: 10.1007/s00382-015-2568-3.
Ming yue, Ch.; Arun K.; Wanqiu, W. (2015). Astudy of the predictability of sea surface temperature over the tropics. Climate Dynamics, 44: 1767–1776. DOI: 10.1007/s00382-014-2187-4.
Nazemosadat, J. (1998). The study of sea surface temperature of the Persian Gulf in on rainfalls in south of Iran. Nivar, 38: 46-33.
Nazemosadat, J.; Ghasemi, M.A.R. (2004). The effect of fluctuations of the Caspian Sea surface temperature on precipitation in the north and southwest areas of Iran. Journal of Science and Technology of Agriculture and Natural Resources, 4: 1-14.
Rao, J.; Rongcai, R. (2015). A decomposition of ENSO’s impacts on the northern winter stratosphere: competing effect of SST forcing in the tropical Indian Ocean. Climate Dynamics, 46: 3689-3707. DOI: 10.1007/s00382-015-2797-5.
Renguang, W.; Song, Y.; Zhiping, W.; Gang, H.; Kaiming, H. (2012).Inter-decadal change in the relationship of southern China summer rainfall with tropical Indo-Pacific SST. Theoretical Applied Climatology, 108: 119-133. DOI: 10.1007/s00704-011-0519-4.
Rezaei, B.; Jahanbakhsh, M.S.; BayatiKhatibi, M.; Zeinali, B. (2010).Prediction of Autumn and Winter rainfall in the Western half of Iran, using the Mediterranean SST in Summer and Autumn. Natural Geographical Studies: 47-62.
Saligheh, M. (2006). Mechanisms of precipitation in the southeast of Iran. Geographical Studies. 55: 1-12.
Shenoi, S.S.C.; Nasnodkar, N.; Rajesh, G.; Jossia, J.K.; Suresh Almeida, A.M. (2009). On the diurnal ranges of Sea Surface Temperature (SST( in the north Indian Ocean. Journal of Earth System Science, 118(5): 483-496. DOI: 10.1007/s12040-009-0038-1.
Zhang, Q.l.; Weng, X.; Cheng, M. (2001). Regional features of long-term SST variation in the western Pacific warm pool area. Chinese Journal of Oceanology and Limnology, 19(4): 312-318. DOI: 10.1007/BF02850734.
Natural Environment Change
Volume 3, Issue 1
Winter & Spring
January 2017
Pages 59-70

Files

Share

How to cite

Statistics