Lucy Oburg Half of the world’s glaciers, particularly the smallest, are at risk of disappearing by the end of this century due to climate change, but limiting climate warming as much as possible helps save other rivers, according to a recent study published yesterday.
This study, published in the prestigious “Science” magazine, presents the most accurate predictions that have been reached to date regarding the future of 215,000 glaciers in the world.
Its authors warn of the importance of taking steps to reduce greenhouse gas emissions responsible for climate change, with the aim of limiting the melting of glaciers and its consequences, such as rising sea levels and a shortage of water resources.
“मुझे लगता है कि हमारे अध्ययन में आशा की एक छोटी सी झलक और एक सकारात्मक संदेश है, क्योंकि यह पुष्टि करता है कि मनुष्य एक अंतर बना सकते हैं और इस मुद्दे को हल करने के लिए कार्रवाई करना महत्वपूर्ण है,” सह-लेखक रेजिन हुक ने एएफपी को बताया।
यह अध्ययन इस तथ्य से अलग है कि इसने बेहतर मार्गदर्शन के लिए ग्लेशियरों पर कई संभावित परिदृश्यों (+1.5°C, +2°C, +3°C, +4°C) के भीतर जलवायु वार्मिंग के प्रत्यक्ष प्रभाव को छुआ। राजनीतिक निर्णय।
If global warming is limited to 1.5°C above pre-industrial levels, the most ambitious target of the Paris climate agreement, 49% of the world’s glaciers will be gone by 2100.
यह नुकसान कुल ग्लेशियर द्रव्यमान का लगभग 26% का प्रतिनिधित्व करता है, क्योंकि छोटी नदियाँ सबसे पहले वार्मिंग से प्रभावित होंगी। शोधकर्ताओं को उम्मीद है कि बर्फ के पिघलने के परिणामस्वरूप समुद्र का स्तर लगभग 9 सेंटीमीटर तक बढ़ जाएगा (एक ऊंचाई जो कि बर्फ की टोपी के पिघलने से जुड़ी हुई है, उदाहरण के लिए)।
“Regions that have relatively low amounts of ice, such as the Alps, the Caucasus, the Andes, or the western United States, will lose almost all of their ice by the end of the century, regardless of the potential associated with emissions,” Regine Hook explains, adding that “these glaciers are threatened in one way or another with extinction.
In the event of climate warming of +4 °C, the worst-case scenario would occur, as larger glaciers such as those in Alaska, for example, would be affected by increasing amounts. And 83% of the glaciers will disappear, or 41% of the total ice mass in the world, while the sea level will rise to 15 centimeters.
“9 and 15 centimeters may not seem like big numbers,” Regine Hook, who devoted her career to studying glaciers to AFP, notes, but these two levels are a cause for “great concern,” because the higher the sea level, the higher it causes floods. during storms, causing “more damage”.
The world is already witnessing severe floods as sea levels rise (3 mm annually)
The complete disappearance of the ice expanses – The world is currently heading towards a warming of +2.7 degrees Celsius, which will lead to the almost complete disappearance of the ice expanses in central Europe, western Canada, the United States, and New Zealand.
These more alarming projections than those of the Intergovernmental Panel on Climate Change are made thanks to recent data on changes in the size of every glacier in the world over recent decades. Based on this data, the researchers were able to better reset the computational model used to predict the future of rivers.
Also, factors not addressed in previous studies were taken into account, including the effect of covering glaciers with debris (rocks…), or the separation of blocks of ice from icebergs.
The glaciers studied represent only “1% of all the ice in the world”, but they are “affected” more than other glaciers, because they are often located in areas where temperatures are recorded close to those on which the ice melts.
Hook points out that these glaciers “have contributed to sea level rise almost as much as the melting of the ice caps in Greenland and Antarctica over the past three decades.”
In addition, the water resources that benefit about two billion people will be affected by the disappearance of the glaciers.
The researcher points out that “glaciers would fill the water shortage in many areas during the summer when they are exposed to heat and drought,” adding that the disappearance of the rivers “will not only cause a change in seasons but will cause a decrease in water quantities.
Also, boat traffic in low-lying rivers and tourism activities around small, easily accessible glaciers will be affected.
Regine Hook asserts that avoiding the disaster is still possible, but that “its occurrence is linked to political officials.”