The Montreal Protocol, which banned most uses of ozone-destroying chemicals known as chlorofluorocarbons (CFCs) and called for their global phase-out by 2010, has been a great success story: Earth’s ozone layer is projected to recover by the 2060s.
So atmospheric chemists were surprised to see a troubling signal in recent data. They found that the levels of five CFCs rose rapidly in the atmosphere from 2010 to 2020. Their results are published today in Nature Geoscience1.
The explosions that blasted holes in the underwater Nord Stream gas pipelines kicked up long-buried toxins at levels high enough to threaten marine life for more than a month, analysis of the site suggests.
Last September, a series of four explosions ruptured the Nord Stream 1 and 2 gas pipelines — which run from Russia to Germany — close to the Danish island of Bornholm in the Baltic Sea, releasing more than 100,000 tonnes of methane into the sea and the atmosphere. It isn’t clear who was behind the explosions, but the most recent speculation is that a pro-Ukrainian group was responsible.
Another round of powerful atmospheric rivers is hitting California, following storms in January and February 2023 that dumped record amounts of snow. This time, the storms are warmer, and they are triggering flood warnings as they bring rain higher into the mountains – on top of the snowpack.
Professor Keith Musselman, who studies water and climate change at the University of Colorado’s Institute of Arctic and Alpine Research, explained the complex risks rain on snow creates and how they might change in a warming climate.
What happens when rain falls on snowpack?
For much of the United States, storms with heavy rainfall can coincide with seasonal snow cover. When that happens, the resulting runoff of water can be much greater than what is produced from rain or snowmelt alone. The combination has resulted in some of the nation’s most destructive and costly floods, including the 1996 Midwest floods and the 2017 flood that damaged California’s Oroville Dam.
Contrary to common belief, rainfall itself has limited energy to melt snow. Rather, it is the warm temperatures, strong winds and high humidity, which can transport substantial energy in the form of latent and sensible heat, that predominantly drive snowmelt during rain-on-snow events.
Researchers have dropped a submersible vehicle down a hole in Antarctic ice to get their closest-ever look at the underside of Thwaites Glacier — a massive and increasingly unstable body of ice that has become an icon of climate change — and the first-ever glimpse at the spot where the ice meets the land.
One of the consequences has been regular flooding, which has claimed lives and property. Over the years, the city authorities have tried to decongest Accra, without success. The city is now demolishing illegal structures, especially those close to waterways.
Some people have suggested that Accra’s congestion problem could be solved if the capital were to be moved to another city. Others disagree.
Take a walk or drive through the streets of most Nigerian cities, and you will see plastic waste everywhere. The country’s rivers, lakes and ocean are also full of discarded plastic. Nigeria is estimated to generate about 2.5 million tonnes of plastic waste annually. Plastic accounts for 15% of the total waste generated in Lagos State.
The situation is likely to worsen as Nigeria’s population grows, from more than 220 million people now to an expected 401 million by the end of 2050.
The production of plastic is growing too. Dangote Refinery, the largest petrochemical refinery in Africa, is starting operations in Nigeria in the first quarter of 2023. Aside from refining fuel, the plant will also produce plastic products.
The United States witnessed an unusual January, characterised by colder-than-normal conditions with rain and ice in the south, warmer-than-normal conditions in the north and record-breaking rains and floods in the west.
Overall, it was the sixth-warmest January on record for the country, according to the National Oceanic and Atmospheric Administration (NOAA).
The new year started off on a wet note for western US, especially California, as the atmospheric rivers that had formed in the last week of December continued to pour rain and snow, causing flash floods and mudslides for three weeks.
More than 1,000km southwest of Mahé, the main inhabited island in Seychelles, lies a ring of coral islands called the Aldabra Atoll. The islands are a Unesco world heritage site and support a huge diversity of marine species including manta rays and tiger sharks.
Aldabra has long been protected from threats to its biodiversity by its remoteness. But now plastic debris is strewn across Aldabra’s coastlines, threatening nearby marine ecosystems. Research finds the likelihood of coral disease increases from 4 per cent to 89 per cent when coral are in contact with plastic.
This article is part of a special edition on the Himalayas, published in February 1-15, 2023, issue of Down To Earth magazine
The last few decades have recorded rapid and magnified natural catastrophes across the world, with scientists linking such extreme events with global warming. The Himalayas have recorded such calamities like earthquakes, avalanches, cloud-bursts, intense rainfall landslide lake outburst floods (LLOFs are breaching of lakes formed by obstructions due to landslides), and glacial lake outburst floods (GLOFs are a sudden release of a significant amount of water retained in a glacial lake) in their most furious forms; ground studies indicate a warming climate as the cause.
The planet has entered the sixth mass extinction. Pollution, climate change and depleting resources could drive up to 27% of the world’s animal life to extinction, a new paper has claimed. The study used a supercomputer to map out how interdependent food chains could collapse in the coming decades.