Heatwave in Bangladesh A Recent and Alarming Phenomenon of Climate Change -Nadira Islam
A heatwave is an extended period of hot weather relative to the expected conditions of the area at that time of year, which may be accompanied by high humidity. A heat wave is an extremely dangerous weather condition where temperatures soar well above 90° F. This high heat combines with high levels of humidity and creates a heat bubble over a certain area for an extended period. A heat wave occurs when static high pressure in the upper atmosphere persists over a region for several days to several weeks. This static high pressure generates a hot mass of air that remains stagnant for many days and weeks, resulting in the trapping of more heat and a reduction in conventional currents.
Events like heat waves have grown to be a real concern, mostly because of their effects on people’s health. The World Meteorological Organization (WMO) reports that between 1991 and 2000, the number of fatalities attributable to extreme heat increased by 2300 percent, with the period from 2001 to 2010 showing by far the highest growth rate for climate-related disasters. Heatwave events continue to be a common trend. Heat waves are expected to last longer, be more intense, and occur more frequently due to climate change brought on by greenhouse gases from burning fossil fuels. When the dust has settled on the heat waves of a particular period, scientists can assess how much human activity has contributed to the issue.
However, researchers have already discovered that humans bear a significant portion of the blame after studying past events and other regions of the world. A study found that climate change increased the likelihood of the heat five times over what it would have been in a world that hadn’t warmed after a summer 2019 heat wave was attributed to 2,500 deaths in Western Europe. As average temperatures have increased, heat waves in the ocean have become 20 times more probable. Additionally, scientists found that there was a 600-fold greater likelihood than not that Siberia would experience a heat wave in 2020 as a result of climate change.
Heat waves were largely considered to be almost independently caused by human activity and unpredictable like earthquakes until the end of the 20th century when they were viewed as a common meteorological fact with major attention paid to drought. According to World Bank and Bangladesh Meteorological Department, the temperature is rapidly increasing per year from 1976 to 2019 and the present year (2022) reached extreme events (above 40 °C based on daily forecasting). The rise in night-time temperatures is particularly worrisome for public health. Because, like most warm-blooded mammals, we cool ourselves by converting sweat into water vapor around a constant body temperature of 37 degrees.
Air pollution worsens as temperatures rise, increasing the rate at which hazards such as ozone form. These pollutants, in turn, aggravate heart and lung problems. The effects of heat wave episodes on the most vulnerable population subgroups, such as children, the elderly, outdoor workers, or residents of urban areas, are of particular concern in climate change-sensitive areas. Dehydration, heat exhaustion, deadly heatstroke, kidney problems, lethargy, and death are just a few of the effects on the majority of the population caused by exposure to extreme heat, along with other side effects like poor work attendance and/or performance among the exposed population.
The rising number of droughts, intense storms, and floods caused by our warming atmosphere poses risks to public health and safety. Prolonged droughts result in more than just scorched lawns. Drought threatens access to safe drinking water, fuels out-of-control wildfires, and causes dust storms, extreme heat events, and flash flooding in many areas. Water scarcity is a leading cause of death and serious disease elsewhere in the world, and it is contributing to crop failure. Heavy rains, on the other hand, cause streams, rivers, and lakes to overflow, causing damage to life and property, contaminating drinking water, causing hazardous-material spills, and promoting mold infestation and unhealthy air. A warmer, wetter world is also beneficial to foodborne and waterborne illnesses, as well as disease-carrying insects like mosquitos, fleas, and ticks.
According to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, the risk of species extinction increases rapidly with rising global temperatures, with invertebrates (particularly pollinators) and flowering plants among the most vulnerable. Climate change is putting stress on the world’s marine ecosystems. Acidification of the oceans poses a serious threat to underwater life, particularly creatures with calcium carbonate shells or skeletons such as mollusks, crabs, and corals. Warmer temperatures can also trigger a cascade of other changes around the world. Because rising air temperatures affect the oceans, weather patterns, snow, and ice, as well as plants and animals. The greater the warming, the more severe the effects on people and the environment.
Reduction and adaptation strategies for heatwave include warning systems of heat health, appropriate urban planning, and building design. The warning system deals with human health and meteorological agencies and is related to targeted advice and intensive measures. The most effective way to mitigate the negative effects of an extreme heat event is to create a comprehensive heat response plan that integrates individual strategies. Forecasting and monitoring, education and awareness, and heat wave response are all possible components of such a plan.
In addition to a comprehensive heat response plan, local officials can help urban areas adapt to extreme heat in the short term by improving infrastructure resilience. Transportation planners can protect or modify roads, bridges, and other structures, for example, by using more resilient and heat tolerant materials, to help these systems withstand higher temperatures and reduce service disruptions. They can also implement energy efficiency and conservation efforts to reduce stress on electricity systems during heat waves and help avoid power outages.
Heat island reduction strategies, such as green or cool roofs, cool pavements, or increased vegetation and trees, can also be incorporated into long-term planning to help reduce temperature extremes during future heat waves. Cool pavements, for example, can be used for roads and parking lots to help cool urban areas because they absorb more solar energy and evaporate less water than traditional materials. Cool or green roofs, as well as planting trees and vegetation, can help keep buildings and their surroundings cooler. These measures also reduce electricity demand, which improves system reliability, especially during heat waves. Adaptations to extreme event situations are physically (reduce health risk), environmentally (use less energy, prevent ecosystem destruction, reduce natural calamities) and socially beneficial for any region as well as Bangladesh. n