A recent study published in Nature Climate Change revealed that, compared to other years on record, the summers of both 2023 and 2024 had nearly 3.5 times more number of marine heatwaves. The increasing number of marine heatwaves increase the frequency and intensity of cyclones, causing loss of ecosystems and infrastructure. Marine heatwaves cause devastating consequences for coral reefs, fisheries and coastal communities. Extreme ocean temperatures turned natural calamities in Asia including Typhoon Doksuri, Severe Cyclonic Storm Remal and Tropical Cyclone Mocha into fatal events for coastal inhabitants. Furthermore, warming of sea water created ‘dead zones’ leading to mass fish deaths and negatively impacted aquaculture in the Gulf of Thailand and the Malacca Straits.In the past two years, climate change, exacerbated by El Niño, caused multiple record-breaking marine heatwaves around the world. The damage done is estimated to be worth many billions of dollars. The study found that between 2023 and 2024, nearly 10 per cent of the ocean hit record high temperatures and also increased the intensity of rainfall by at least 10 per cent. Scientists warned that as long as the rate of human-induced climate change keeps rising, marine heatwaves will continue to worsen. More proactive action is needed to avert the damage that extreme ocean temperatures already cause, the researchers noted. The study cites examples of the tragic consequences of marine heatwaves on humans and the ecology. In 2023, a heatwave fuelled Cyclone Gabrielle claimed 11 human lives and caused damages worth over USD 8 billion in New Zealand. Between 2023 and 2024, displacement of Peruvian anchovies from their usual waters due to marine heatwaves led to the closure of commercial fisheries with estimated losses of USD 1.4 billion. In 2023, heavy rains from Storm Daniel in Libya caused the collapse of the Derna Dam; the resulting event has been recorded as the deadliest single flood in the history of Africa, killing 6,000 people. The ocean is vital for regulating the climate and supporting marine life, in turn providing food and livelihood for billions of people. However, these functions are at risk as marine heatwaves worsen with climate change, researchers say. “In the past two years, marine heatwaves have forced the closure of fisheries and aquaculture, increased whale and dolphin strandings, and caused the fourth global coral bleaching event,” said Alex Sen Gupta of Climate Change Research Centre, Centre for Marine Science & Innovation and ARC Centre of Excellence for Climate Extremes, University of New South Wales, Australia.Scientists noted that good forecasting and prompt action reduced the impacts of some marine heatwaves. “Better forecasting and rapid response plans could have reduced impacts in other regions,” Sen Gupta adds, a co-author of the paper.
Source link
