RISAT-2B satellite launched on May 22 will use microwave radiation for crop monitoring, forestry and flood mapping. The satellite can image during day and night and under almost all weather conditions including cloud cover. It can detect objects with dimensions of as little as a metre, making it ideal for military surveillance. With the successful … Continue reading Surveillance from the sky using RISAT-2B satellite
Flood
A rare confluence of four events led to flooding in Kerala, IIT Gandhinagar researchers say
A deadly combination of four factors caused extensive flooding in Kerala in 2018. The State received 53% above normal summer monsoon rainfall from May to August. This together with a few extreme rainfall events covering almost the entire State, six of the seven major reservoirs with over 90% storage before the extreme rainfall events, and catchment areas of major reservoirs … Continue reading A rare confluence of four events led to flooding in Kerala, IIT Gandhinagar researchers say
Extreme rainfall events pose a challenge to reservoir operations
Modelling studies by IIT Ghandhinagar team has found that if high emission continues, then by the end of the century the mean annual air temperature is projected to increase up to 6.25 degree C, while rainfall in the catchments is likely to rise by 13-18%. There is a need to improve prediction skill of extreme rainfall events … Continue reading Extreme rainfall events pose a challenge to reservoir operations
Short, heavy spells get a new name – mini-cloud burst
Researchers at Indian Institute of Tropical Meteorology, Pune have coined a new term — mini-cloud burst — to define rainfall in excess of 50 mm in two consecutive hours. While extreme rainfall of over 200 mm in 24 hours translates to only 16 mm rainfall per hour, the intensity of rainfall is far more in the case of mini-cloud … Continue reading Short, heavy spells get a new name – mini-cloud burst
Two-fold increase in short spells of heavy rainfall in Indian cities
Very heavy rainfall lasting for a few hours in urban locations in India has become more intense in the last few decades. Its frequency has increased by two-fold between 1979-2015. Cities get flooded quickly following heavy downpour lasting a few hours. So it is necessary to record the amount of rainfall every 15 minutes in … Continue reading Two-fold increase in short spells of heavy rainfall in Indian cities
Three-fold increase in extreme rainfall events over central India
Summer monsoon rainfall over central India has reduced by 10% on average, while there has been three-fold increase in extreme rainfall events between 1950 and 2015. There will be further increase in extreme rainfall events over most parts of the Indian subcontinent by the end of the century. There has been an average 10% decline in … Continue reading Three-fold increase in extreme rainfall events over central India
Scientists now know why Chennai received unprecedented heavy rainfall in 2015
Both extreme El Nino conditions and the warming trend in the Bay of Bengal contributed equally to the Chennai deluge. The extreme El Nino conditions in 2015 and the warming trend in the Bay of Bengal contributed equally to the unprecedented heavy rainfall witnessed in Chennai for three days from November 30 to December 2, 2015, … Continue reading Scientists now know why Chennai received unprecedented heavy rainfall in 2015
IIT Bombay: Extreme rainfall not associated with local warming
A study carried out by researchers at IIT Bombay has found that extreme rainfall events over India do not have significant association with land surface air temperature over India and sea surface temperature over central Indian Ocean. The results are contrary to the general notion that global warming or increased summer temperature is responsible for … Continue reading IIT Bombay: Extreme rainfall not associated with local warming
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