Extreme Climate Event Footprint at Delhi, India: A Comparison of Last One Decade Meteorological Conditions

Article type: Research Article

Authors: Ranjan, Shyam^a | Ramanathan, AL.^{a; *} | Singh, Virendra Bahadur^b

Correspondence: [*] Corresponding Author. alrjnu@gmail.com

Abstract: Rapid urbanization and rise of greenhouse gaseous emission due to anthropogenic influences have increased the pressure on global climate to maintain its equilibrium. Anthropogenic influences have further increased the extreme events, i.e., heat wave, flash flood and cold wave event. Our results indicate that years 2012, 2015 and 2016 encountered with heat wave event while the year 2013 recorded the highest precipitation which is coinciding with the well known flash flood event in northern India (Uttarakhand) where intense precipitation with cloud burst occurred. Correlation and wavelet coherence analysis was performed among temperature (T), relative humidity (RH), wind speed (WS), precipitation (ppt), potential evapotranspiration (PET) and actual evapotranspiration (AET). PET shows strong association with T during the heatwave event while AET exhibits the strong association during the flash flood event. T and RH show the time lag at averaged monthly scale where T attains its peak during the summer time while RH attains its peak during the monsoon time. The highest coefficient of variation (COV) shown by ppt is due to its dependency on Indian Summer Monsoon (ISM) during the monsoon time. We have further analysed the monthly amplitudinal variation of all parameters in order to observe the seasonality. Furthermore, wavelet coherence analysis was also performed to see the dependency among all parameters at high temporal scale.

Keywords: Extreme event, Heatwave, Flash flood

DOI: 10.3233/JCC190004

Journal: Journal of Climate Change, vol. 5, no. 1, pp. 33-40, 2019