Palash, a PhD researcher on meteorology and climate at the University of Saskatchewan in Canada, discusses the impact of cyclones, the role of the Bangladesh Meteorological Department (BMD), and seasonal cyclone trends, among other matters.
How well did the BMD perform ahead of Cyclone Sitrang?
Unfortunately, the BMD performed very poorly in providing a forecast of Cyclone Sitrang to the Bangladeshi people with sufficient lead time. In fact, BMD gave a forecast on October 22, four days after a low-pressure system formed on October 18. Right at that moment, I cannot remember any strength of BMD. There are many weaknesses of BMD, including a lack of human resources with at least one meteorology or atmospheric science degree, absence of broadcast meteorologist, very old-fashioned forecast communication techniques, poorly managed weather instruments (for example, most of the Radars are non-operational), and limited meteorological observational stations, etc. The above-listed issues need to be solved immediately to ensure effective and efficient weather forecasting.
Is there any possibility of another cyclone in December?
In the Bay of Bengal, there are two Cyclone seasons in a year. The first season ranges from April to June, and the second from October to December. It is to be noted that cyclones rarely form in the northern Bay of Bengal before the third week of October, because monsoon circulation recedes only after October 15. Furthermore, Cyclones do not hit the north Bay of Bengal after the second week of December as the sea surface temperature becomes too cold to support Cyclone development and maintenance. Therefore, a cyclone forming in the first two weeks of December is possible, but the chance of cyclone development in December is very low. Instead of December, the chance of Cyclone development in the last ten days of November is comparatively high.
CollectedHave cyclones been occurring more frequently in recent years due to climate change?
Scientists need observational cyclone data for 100 to 200 years to identify a statistically significant trend in Cyclone frequency in the global oceans. Unfortunately, a lack of high-quality and long-duration cyclone data sets prevents scientists from drawing any relationship between cyclone frequency and climate change. Instead of cyclone frequency, scientists have found strong evidence of the impact of global warming in cyclone strength, cyclone movement speed (translational speed), and rainfall amount. Scientists have found that the anthropogenic warming of the atmosphere has been making cyclones stronger in recent decades. Moreover, Cyclones are taking more time to make landfall. Cyclones have been moving more slowly in recent decades compared to earlier decades. Since cyclones take more time to make landfall, cyclones in recent decades have produced more rainfall than before.
What will happen in the next 10 to 20 years in terms of extreme weather events like cyclones, flash floods, untimely rain, and droughts?
Most tropical cyclone experts agree that, in general, people will witness stronger cyclones more frequently, producing a massive amount of rainfall and resulting in catastrophic damage to lives and property. Because of global warming, the atmosphere is holding more water vapor than 30 years ago. Thus, thunderstorms or cyclones are producing higher rainfall in total nowadays than before. According to an Intergovernmental Panel on Climate Change (IPCC) report, wet areas will get wetter, and dry areas will become drier. That means wet places like Bangladesh will get more rainfall in the future, and dry regions like sub-Saharan countries (Mali, Sudan, Libya, etc.) will get drier.