Scientists say that the past two years have been the warmest on record for the planet, with global temperatures more than 1.5 degrees Celsius above preindustrial for extended periods. This global warmth is now reflected in the oceans around the Antarctic.
|Last Updated: Sep 10, 2024, 06:27 PM IST|Source: IANS
Eldorado Do Sul: Rescuers rushed to evacuate people stranded by devastating floods across the southern Brazilian state of Rio Grande do Sul on Tuesday, with at least 90 dead, thousands left homeless, and desperate survivors seeking food and basic supplies. On the outskirts of Eldorado do Sul, 17 kilometers (10.5 miles) from the state capital of Porto Alegre, many people were sleeping on the roadside and told Reuters they were going hungry. Entire families were leaving on foot, carrying belongings in backpacks and shopping carts.
“We’ve been without food for three days and we’ve only just got this blanket. I’m with people I don’t even know, I don’t know where my family is,” said a young man who gave his Name as Ricardo Junior.
The flooding has hampered rescue efforts, with dozens of people still waiting to be evacuated by boat or helicopter from stricken homes. Small boats crisscrossed the flooded town searching for survivors. The state’s Civil Defense agency said the death toll had risen to 90 with another four deaths being investigated, while 131 people were still unaccounted for and 155,000 homeless.
The heavy rains that began last week have caused rivers to flood, inundating whole towns and destroying roads and bridges.Rain is forecast to let up on Thursday but then continue through the weekend.
Climate experts attributed the extreme rainfall in Rio Grande do Sul to the confluence of a heatwave caused by this year’s El Niño phenomenon, which warms the waters of the Pacific and brings rain to southern Brazil; a weaker cold front with rain and gales coming from the Antarctic; and unusual warmth in the Atlantic also raising humidity.
Global warming exacerbates these phenomena and intensifies the effects between such systems, making weather unpredictable, said Marcelo Schneider, a National Meteorology Institute (Inmet) researcher.
ELECTRICITY CUTS
In Porto Alegre, a city of 1.3 million inhabitants, downtown streets were under water after the Guaiba River breached its banks with record water levels.
Porto Alegre residents faced empty supermarket shelves and closed gas stations, with shops rationing sales of mineral water. The city distributed water in trucks to hospitals and shelters.
The floods have also impacted water and electricity services, with more than 1.4 million affected overall, according to Civil Defense. Almost half a million people were without power in Porto Alegre and outlying towns as electricity companies cut off supplies for security reasons in flooded neighborhoods. National grid operator ONS said five hydroelectric dams and transmission lines were shut down due to the heavy rains. The city’s airport, its apron under water, has suspended all flights since Friday.
Fuel shortages were reported as state-run oil company Petrobras said it was having trouble moving diesel from its refinery in badly-flooded Canoas within metropolitan Porto Alegre, a senior government official said.
President Luiz Inacio Lula da Silva said on a government television program that the extent of the damage will not be known until the waters subside. He promised federal aid for the state in what is considered its worst ever climate disaster. JP Morgan economists projected that the impact of the floods on Brazil’s economy would be a modest dent in GDP growth and a marginal increase in inflation, mainly due to higher prices for rice that is largely produced in Rio Grande do Sul. The government said Brazil will import rice to stabilize the market.
Besides destroying critical infrastructure, the heavy rains and flooding have left grains fields under water and killed livestock, interrupting the soy harvest and halting work at multiple meat plants.
The Rio Grande port, a major port for grain exports, was operating normally, the state’s port authority said. However, main access roads were impassable, disrupting grain deliveries to the port as trucks had to make a wide detour, exporters said.
New Delhi: The latest satellite images shared by the Indian Space Research Organisation (ISRO)have raised concern globally as it show a significant expansion of the glacial lakes in the Himalayas in the past 3 to 4 decades. According to ISRO’s data, over 600 lakes which amount to 89% of the total glacial lakes on the Himalayas have grown over twice their size in the past 30- 40 years.
Long-term changes in the Ghepang Ghat glacial lake (Indus River Basin) at an elevation of 4,068 m in Himachal Pradesh, India, show a 178 per cent increase in size from 36.49 to 101.30 hectares between 1989 and 2022. The rate of increase is about 1.96 hectares per year.
Long-term satellite imagery covering the catchments of Indian Himalayan river basins from 1984 to 2023 indicates significant changes in glacial lakes. Of the 2,431 lakes larger than 10 hectares identified during 2016-17, 676 glacial lakes have notably expanded since 1984. Specifically, 130 of these lakes are situated within India, with 65, 7, and 58 lakes located in the Indus, Ganga, and Brahmaputra River basins, respectively, the statement read.
The Himalayan Mountains are often referred to as the Third Pole because of their extensive glaciers and snow cover. They are considered highly sensitive to changes in the global climate, both in terms of their physical characteristics and their societal impacts.
Research conducted worldwide has consistently shown that glaciers across the globe have been experiencing unprecedented rates of retreat and thinning since the onset of the Industrial Revolution in the eighteenth century.
This retreat leads to the formation of new lakes and the enlargement of existing ones in the Himalayan region. These bodies of water, created by the melting of glaciers, are known as glacial lakes and play a crucial role as freshwater sources for rivers in the Himalayan region.
However, they also pose significant risks, such as Glacial Lake Outburst Floods (GLOFs), which can have devastating consequences for communities downstream. GLOFs occur when glacial lakes release large volumes of meltwater due to the failure of natural dams, such as those made of moraine or ice, resulting in sudden and severe flooding downstream, ISRO further stated.
These dam failures can be triggered by various factors, including avalanches of ice or rock, extreme weather events, and other environmental factors. Monitoring and studying the occurrence and expansion of glacial lakes in the Himalayan region is considered challenging due to the inaccessible and rugged terrain.
Satellite remote sensing technology proves to be an excellent tool for inventory and monitoring due to its wide coverage and revisit capability, the ISRO stated, adding that assessing long-term changes in glacial lakes is crucial for understanding glacier retreat rates, assessing GLOF risks, and gaining insights into climate change impacts.
Elevation-based analysis further reveals that 314 lakes are located in the 4,000 to 5,000 m range and 296 lakes are above 5,000 m elevation. The glacial lakes are categorized based on their formation process into four broad categories, namely Moraine-dammed (water dammed by moraine), Ice-dammed (water dammed by ice), Erosion (water dammed in depressions formed by erosion), and other glacial lakes. Among the 676 expanding lakes, the majority of them are Moraine-dammed (307) followed by Erosion (265), other (96), and Ice-dammed (8) glacial lakes, respectively, the release further stated.
Satellite-derived long-term change analyses provide valuable insights for understanding glacial lake dynamics, which are essential for assessing environmental impacts and developing strategies for GLOF risk management and climate change adaptation in glacial environments, it added.