Girona in Catalonia in Spain experienced its highest ever temperature at 45.3 degrees Celsius, while Verdun in Northwest France saw its historic high at 40.6 degrees Celsius. In China, on the other hand, Sanbao in Xinjian recorded more than 52 degrees Celsius on Sunday (July 16). On the same day, a coastal airport in Persian Gulf region in Iran was hit by a heatwave that raised temperature to as high as 66.66 degrees Celsius.The extreme heat is at the same time a severe public health hazard and a threat to the economic output. American doctors have cautioned that 90 million people are at risk of being exposed to extreme heatwave. Last month the heatwave took its toll in parts of the South and Midwest of the USA claiming more than a dozen lives. Of the 882 active wildfires now raging in Canada, 579 are thought to be out of control.
Bangladesh saw its longest spell of severe heatwave (temperatures ranging from 40 degrees Celsius to 41.9 degrees Celsius) six days at a stretch in the first week of June. While on April 17 this year, the highest ever temperature at 43 degrees Celsius was recorded at Iswardi in Pabna district.
So, has then the UN climate summits' goal of holding the increase in global average temperature to below 2.0 degrees Celsius above the pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degrees Celsius above the pre-industrial levels (limit set at the so-called Paris Agreement of 2015) no relevance now? Has Nature acted faster than the climate scientists had thought? Well, to be frank, climate scientists are not sure. In fact, climate change is an unbelievably complex subject. Being still in its infancy, climate science is yet to come up with a sure-fire answer to this question. Even so, scientists believe there are two drivers of the ongoing heatwaves: the usual climate change and the phenomenon of El Nino.
El Nino is unusual warming of water surface in the eastern equatorial Pacific Ocean that happens, though irregularly, every two to seven years. It raises temperatures in different parts of the world, causes tropical cyclones in the Pacific and increases flood risks and rainfall in parts of the Americas as well as elsewhere in the world. Scientists at the US National Oceanic and Atmospheric Administration (NOAA) have meanwhile declared that the El Nino is already under way. If so-and, to all appearances, it already is-then, the rest of the world including Bangladesh has already begun to experience it in the form of the extreme heatwaves, heavy downpours, floods as well as prolonged drought situations. Bangladesh is already going through such a situation. In June, the country experienced a low rainfall pattern which was 16 per cent below the normal. In the current month the situation is far worse and according to the Bangladesh Meteorological Department (BMD), rainfall is 67 per cent below the normal pattern. The extreme weather condition affected production of Aus crop. The literally skyrocketing price of chili is linked to this abnormal weather condition of low rainfall and heatwave. Production of other summer vegetables, cash crops like jute and fruits is also being adversely impacted by this weather condition triggered by global warming in association with El Nino.
What is further worrying is that pest attacks on crops are also increasing in concert with changed weather pattern. It is not only food production that is under threat from this erratic weather pattern, it is also behind public health hazards caused by insects like mosquitoes. For the World Health Organization (WHO) has warned that dengue fever cases may see nearly a record high this year globally due to global warming that helps mosquitoes to spread. Interestingly, a temperature level of over 45 degrees Celsius should kill the mosquitoes rather than help them breed. But that is not happening. How so? Dr Raman Velayudhan, a WHO specialist, is of the view that the mosquitoes are very clever in finding ways to beat the extreme temperature. So, compared to 2000, dengue incidence was up eightfold at 4.2 million cases in 2022. Europe, too, saw a sharp rise in the number of dengue cases, while Peru in South America even declared a state of emergency over dengue. In January 2023, WHO warned that dengue represented a 'pandemic threat'as it was the world's fastest growing tropical disease.
To combat dengue, Argentina in South America, which has suffered its worst dengue outbreaks in recent years, has been sterilising mosquitoes by subjecting them to radiation that alters their (the mosquitoes') DNA. The mosquitoes thus sterilised are being released into the wild. Seeing that Bangladesh at the moment is experiencing an alarming rise in the number of dengue cases with attendant fatalities, can't those engaged in fighting dengue and its cause, the Aedes Aegypti, in Bangladesh learn from Argentinian experience?
Everything, from food security to public health, seems to be in the crosshairs of climate change and El Nino. Hopefully, policymakers in Bangladesh are aware of the gravity of the situation and are up to the challenges facing them.
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