Oceans bearing the brunt of climate change caused by greenhouse gas emissions

Oceans have absorbed the vast majority of the warming caused by burning fossil fuels and shielded societies from the full impact of greenhouse gas emissionsBut this crucial ally has developed alarming symptoms of stress heatwaves loss of marine life rising sea levels falling oxygen levels and acidification caused by the uptake of excess carbon dioxideThese effects risk not just the health of the ocean but the entire planet Heating up By absorbing more than 90 percent of the excess heat trapped in the atmosphere by greenhouse gases oceans are warming faster and faster said Angelique Melet an oceanographer at the European Mercator Ocean monitorThe UNs IPCC climate expert panel has said the rate of ocean warming and therefore its heat uptake has more than doubled since 1993Average sea surface temperatures reached new records in 2023 and 2024Despite a respite at the start of 2025 temperatures remain at historic highs according to data from the Europe Unions Copernicus climate monitorThe Mediterranean has set a new temperature record in each of the past three years and is one of the basins most affected along with the North Atlantic and Arctic oceans said Thibault Guinaldo of Frances CEMS research centreMarine heatwaves have doubled in frequency become longer lasting and more intense and affect a wider area the IPCC said in its special oceans reportWarmer seas can make storms more violent feeding them with heat and evaporated waterThe heating water can also be devastating for species especially corals and seagrass beds which are unable to migrateFor corals between 70 percent and 90 percent are expected to be lost this century if the world reaches 15 degrees Celsius 27 degrees Fahrenheit of warming compared to preindustrial levelsScientists expect that threshold the more ambitious goal of the Paris climate deal to be breached in the early 2030s or even before Relentless rise When a liquid or gas warms up it expands and takes up more spaceIn the case of the oceans this thermal expansion combines with the slow but irreversible melting of the worlds ice caps and mountain glaciers to lift the worlds seasThe pace at which global oceans are rising has doubled in three decades and if current trends continue it will double again by 2100 to about one centimetre per year according to recent researchAround 230 million people worldwide live less than a metre above sea level vulnerable to increasing threats from floods and stormsOcean warming like sealevel rise has become an inescapable process on the scale of our lives but also over several centuries said MeletBut if we reduce greenhouse gas emissions we will reduce the rate and magnitude of the damage and gain time for adaptation More acidity less oxygen The ocean not only stores heat it has also taken up 20 to 30 percent of all humans carbon dioxide emissions since the 1980s according to the IPCC causing the waters to become more acidicAcidification weakens corals and makes it harder for shellfish and the skeletons of crustaceans and certain plankton to calcifyAnother key indicator is oxygen concentration which is obviously important for marine life said MeletOxygen loss is due to a complex set of causes including those linked to warming waters Reduced sea ice Combined Arctic and Antarctic sea ice cover frozen ocean water that floats on the surface plunged to a record low in midFebruary more than a million square miles below the pre2010 averageThis becomes a vicious circle with less sea ice allowing more solar energy to reach and warm the water leading to more ice meltingThis feeds the phenomenon of polar amplification that makes global warming faster and more intense at the poles said GuinaldoThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever