Lightning and climate: A review

Observation of the vertical profile of precipitation over the global Tropics is a key objective of the Tropical Rainfall Measuring Mission (TRMM) because this information is central to obtaining vertical profiles of latent heating. This study combines both TRMM precipitation radar (PR) and Lightning Imaging Sensor (LIS) data to examine “wet-season” vertical structures of tropical precipitation across a broad spectrum of locations in the global Tropics. TRMM-PR reflectivity data (2A25 algorithm) were utilized to produce seasonal mean three-dimensional relative frequency histograms and precipitation ice water contents over grid boxes of approximately 5°–10° in latitude and longitude. The reflectivity histograms and ice water contents were then combined with LIS lightning flash densities and 2A25 mean rainfall rates to examine regional relationships between precipitation vertical structure, precipitation processes, and lightning production. Analysis of the reflectivity vertical structure histograms ...

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Regional Variability in Tropical Convection: Observations from TRMM

Previous total lightning climatology studies using Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor (LIS) observations were reported at coarse resolution (0.5°) and employed significant spatial and temporal smoothing to account for sampling limitations of TRMM’s tropical to subtropical low-Earth-orbit coverage. The analysis reported here uses a 16-yr reprocessed dataset to create a very high-resolution (0.1°) climatology with no further spatial averaging. This analysis reveals that Earth’s principal lightning hotspot occurs over Lake Maracaibo in Venezuela, while the highest flash rate density hotspot previously found at the lower 0.5°-resolution sampling was found in the Congo basin in Africa. Lake Maracaibo’s pattern of convergent windflow (mountain–valley, lake, and sea breezes) occurs over the warm lake waters nearly year-round and contributes to nocturnal thunderstorm development 297 days per year on average. These thunderstorms are very localized, and their persistent deve...

Where Are the Lightning Hotspots on Earth

Assessment of Climate Change over the Indian Region : A Report of the Ministry of Earth Sciences (MoES), Government of India

The seasonally and diurnally varying frequency of lightning flashes provides a measure of the frequency of occurrence of intense convection and, as such, is useful in describing the Earth's climate. Here we present a few highlights of a global lightning climatology based on data from the ground-based World Wide Lightning Location Network (WWLLN), for which global observations began in 2004. Because WWLLN monitors global lightning continuously, it samples ~100 times as many lightning strokes/flashes per year as the Tropical Rainfall Measuring Mission's (TRMM) Lightning Imaging Sensor (LIS). Using WWLLN data it is possible to generate a global lightning climatology that captures seasonal variations, including those associated with the midlatitude storm tracks, and resolves the diurnal cycle, thereby illuminating the interplay between sea breezes, mountain–valley wind systems, and remotely forced gravity waves in touching off thunderstorms in a wide variety of geographical settings. The text of the paper sho...

Highlights of a New Ground-Based, Hourly Global Lightning Climatology

This paper describes the results of monthly latitudinal (8Â°-30Â° N) and latitude belts (8Â°-10Â°, 10Â°-15Â°, 15Â°-20Â°, 20Â°-25Â°, and 25Â°-30Â°N) averaged seasonal thunderstorm activity over India by using monthly data from a large number of Indian stations from 1970 to 1980. The latitudinal variation in the premonsoon (March-April-May) and monsoon season (June-September) months is described and the results are discussed. An examination of the seasonal thunderstorm day activity in the first four belts indicated systematic changes in their signals of semiannual oscillation. These changes are noted to be a function of latitude and season and appear to be consistent with the seasonal migration of the Intertropical Convergence Zone and solar heating of the Indian landmass. We compare the thunderstorm day activity with the monthly mean maximum values of the surface wet-bulb (Tw) temperatures in the five latitude belts over the Indian region. By using rainfall data for the same period of study, the relationship between seasonal rainfall and number of thunderstorm days over the 11 year period is examined. The results of variation of the ratio of monthly rainfall to thunderstorm days (RTR) during different phases of the southwest monsoon are also presented. Results of the monthly mean electrical conditions of mesoscale and isolated deep convective storms at Pune are summarized. It is noted that the electrification of the premonsoon season thunderstorms dominated by a factor of 3-4 over the monsoon ones. We have examined at length the possible influence of the El Nino on the occurrence and electrification of thunderstorms over the Indian region.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/98JD02592

Thunderstorm activity over India and the Indian southwest monsoon

[1] Spatio-temporal variability of lightning activity over the Indian land mass region (8°N–33°N, 73°E–86°E) has been studied using monthly satellite based lightning flash grid (5° × 5°) data for 5-year (1998–2002) period. These data have been examined for depicting the annual, seasonal, and spatial distribution of the lightning activity. The study revealed the nonlinear relationship between lightning flash density and latitude on the annual timescale, and it is linked with the convective activity, large-scale circulations, land mass gradient, and orography of the region under study. On the seasonal timescale, the nonlinear positive relationships were observed in the premonsoon and monsoon seasons whereas a bimodal variation is observed in the post-monsoon season. The comparison of flash density with maximum surface air temperature shows the existence of nonlinear relationship between the two parameters. The approximate range of increase of flash density per 1°C rise in temperature is 20 to 44%. The lightning flash density shows a pronounced semiannual oscillation over the latitude belts 8°N–28°N.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2004JD005631

Spatio-temporal variability of lightning activity over the Indian region

[1] Satellite (LIS) based lightning flash grid (0.5° × 0.5°) data for the Indian land mass region covering from 8°–33°N and 73°–86°E for a period of 4 years (1998–2001) were used to study the diurnal variation with one hour time resolution. The analysis revealed that there exists a strong diurnal cycle in the lightning activity with a prominent peak around 1000 UTC. An examination of seasonal diurnal variation suggests that the lightning activity was found highest in premonsoon and lowest in the postmonsoon season.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2003GL018005

Diurnal variation of lightning activity over the Indian region

Thirty years (1951-1980) of mean monthly thunderstorms days (TS) and rainfall (RF) amounts for 260 Indian observatories spread uniformly over the country were used to obtain their monthly, seasonal and zonal percentage of occurrence from all India totals. The study has revealed that there is a time lag of one month in the occurrence of peak activity of TS and RF. Seasonal analysis of these two parameters suggest that rainfall yield associated with postmonsoon season TS seems to be higher than the premonsoon season. Six zone analysis of TS and RF has suggested that there exists a wide range of variation in both parameters month after month in that zones, but the 30 year mean percentage of occurrence seems to be more or less equal in magnitude in each zone.

/pdf/study-of-thunderstorm-and-rainfall-activity-over-the-indian-14lcbaywx8.pdf

Study of thunderstorm and rainfall activity over the Indian region

Land-ocean contrasts in the lightning activity over Indian land and two surrounding oceanic regions viz. Arabian Sea and Bay of Bengal have been studied. Satellite-based lightning flash data for 5-year (1998–2002) period have been used. The study revealed that lightning activity over Bay of Bengal was three times higher than that over Arabian Sea and 9.3 times lower than that over land. The bimodal distribution is seen over Arabian Sea (peaks in April and November), and land (peaks in May and September). A unimodal distribution is observed over Bay of Bengal with peak in May. The maximum activity over Bay of Bengal occurs more at northern latitudes (28–30°N) compared with Arabian Sea (12–14°N). The land–ocean contrast is dominated by monsoon season. Comparison of lightning activity in the El Nino (2002) and La Nina year (1998–2001) shows that the lightning activity is increased by nearly 18% over the land region and it maybe attributed to in the increase in surface air temperature during the warm phase of El Nino, land sea breeze circulations and difference in the continental and the oceanic convection. Copyright © 2009 Royal Meteorological Society

S. S. Kandalgaonkar

Papers

Thunderstorm activity over India and the Indian southwest monsoon

Spatio-temporal variability of lightning activity over the Indian region

Diurnal variation of lightning activity over the Indian region

Study of thunderstorm and rainfall activity over the Indian region

Land‐ocean contrasts in lightning activity over the Indian region