The glaciers of Alaska are melting and retreating: the chief cause is climate change and the loss of ice is unlikely to slow, according to a new study by U.S. scientists.
They calculate that the frozen rivers of the Pacific coast of America’s northernmost state are melting fast enough to cover the whole of Alaska with 30 centimeters of water every seven years.
Since Alaska is enormous—it covers 1.5 million square kilometers and is the size of California, Texas and Montana put together—this adds up to a significant contribution to sea level rise.
“The Alaska region has long been considered a primary player in the global sea level budget, but the exact details of the drivers and mechanisms of Alaska glacier change have been stubbornly elusive,” said Chris Larsen, a geophysicist at the University of Alaska Fairbanks, and lead author of a study in Geophysical Research Letters.
Taxonomy of change
Scientists from the University of Alaska and the U.S. Geological Survey analyzed studies of 116 glaciers in the Alaska region over a 19-year-period to estimate the rate at which ice melted and icebergs calved.
They used airborne lidar remote sensing technology and other techniques, historical data and a global glacier inventory to establish a kind of taxonomy of glacier change.
The Columbia Glacier in Prince William Sound had retreated more than 19 kilometers because of iceberg calving and had thinned by 450 meters in height since 1980. But, unexpectedly, tidewater glaciers—those that end in the ocean—seemed to make comparatively little contribution to sea level rise.
“Instead we show that glaciers ending on land are losing mass exceptionally fast, overshadowing mass changes due to iceberg calving, and making climate-related melting the primary control on mountain glacier mass loss,” Larsen said.
Big contributor
He and his colleagues calculated that Alaska is losing ice at the rate of 75 billion metric tons a year. Such research is just one more piece of careful cross-checking in the great mosaic of climate research: another systematic confirmation that overall, glaciers are not losing ice in response to some natural cycle of change of the kind that occasionally confuses the picture for climate science.
The agency at work is largely global warming as a response to the steady rise in atmospheric carbon dioxide as a consequence of the burning of fossil fuels.
Mountain glaciers represent only one percent of the total ice on the planet: the other 99 percent is found in Greenland—which is melting fast—and in the great frozen continent of Antarctica, where ice mass is being lost at an increasing rate.
But although the mountains of the temperate and tropic zones bear only a tiny percentage of the planet’s ice, their melting accounts for almost a third of the sea level rise currently measured by oceanographers, and this melting will go on to become a big contributor to the sea levels later this century.
Across the border in Canada, glaciologists have warned that the country will lose a huge volume of flowing ice, and while one team has confirmed that air pollution rather than global warming long ago began to strip Europe’s Alps of their glaciers, in general mountain peaks are warming faster than the valleys and plains below them.
Geophysicists and glaciologists have established that the glaciers of the tropical Andes are at risk, and in the Himalayan mountain chain glaciers seem to be in inexorable retreat with consequences that could be devastating for the many millions in the Indian subcontinent and in China who rely on seasonal meltwater for agriculture.
Glaciers are by definition hard to study—they are high, cold and in dangerous terrain—and such research is inevitably incomplete: the scientists, for instance, excluded glaciers smaller than three square kilometers. But together these small patches of flowing ice account for 16 percent of Alaska’s glaciated landscape. The 116 glaciers in the survey together added up to only 41 percent of the state’s glaciated area.
But the pattern established by the Fairbanks team suggests that melting will accelerate with climate change. “Rates of loss from Alaska are unlikely to decline, since surface melt is the predominant driver, and summer temperatures are expected to increase,” said Dr Larsen.
“There is a lot of momentum in the system, and Alaska will continue to be a major driver of sea level change in the upcoming decades.”
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Though made in large part of plastic, glass, ceramics, gold and copper, they also contain critical resources. The gallium used for LEDs and the camera flash, the tantalum in capacitors and indium that powers the display were all pulled from the ground — at a price for nature and people.
"Mining raw materials is always problematic, both with regard to human rights and ecology," said Melanie Müller, raw materials expert of the German think tank SWP. "Their production process is pretty toxic."
The gallium and indium in many phones comes from China or South Korea, the tantalum from the Democratic Republic of Congo or Rwanda. All in, such materials comprise less than ten grams of a phone's weight. But these grams finance an international mining industry that causes radioactive earth dumps, poisoned groundwater and Indigenous population displacement.
Environmental Damage: 'Nature Has Been Overexploited'
The problem is that modern technologies don't work without what are known as critical raw materials. Collectively, solar panels, drones, 3D printers and smartphone contain as many as 30 of these different elements sourced from around the globe. A prime example is lithium from Chile, which is essential in the manufacture of batteries for electric vehicles.
"No one, not even within the industry, would deny that mining lithium causes enormous environmental damage," Müller explained, in reference to the artificial lakes companies create when flushing the metal out of underground brine reservoirs. "The process uses vast amounts of water, so you end up with these huge flooded areas where the lithium settles."
This means of extraction results in the destruction and contamination of the natural water system. Unique plants and animals lose access to groundwater and watering holes. There have also been reports of freshwater becoming salinated due to extensive acidic waste water during lithium mining.
But lithium is not the only raw material that causes damage. Securing just one ton of rare earth elements produces 2,000 tons of toxic waste, and has devastated large regions of China, said Günther Hilpert, head of the Asia Research Division of the German think tank SWP.
He says companies there have adopted a process of spraying acid over the mining areas in order to separate the rare earths from other ores, and that mined areas are often abandoned after excavation.
"They are no longer viable for agricultural use," Hilpert said. "Nature has been overexploited."
China is not the only country with low environmental mining standards and poor resource governance. In Madagascar, for example, a thriving illegal gem and metal mining sector has been linked to rainforest depletion and destruction of natural lemur habitats.
States like Madagascar, Rwanda and the DRC score poorly on the Environmental Performance Index that ranks 180 countries for their effort on factors including conservation, air quality, waste management and emissions. Environmentalists are therefore particularly concerned that these countries are mining highly toxic materials like beryllium, tantalum and cobalt.
But it is not only nature that suffers from the extraction of high-demand critical raw materials.
"It is a dirty, toxic, partly radioactive industry," Hilpert said. "China, for example, has never really cared about human rights when it comes to achieving production targets."
Dirty, Toxic, Radioactive: Working in the Mining Sector
One of the most extreme examples is Baotou, a Chinese city in Inner Mongolia, where rare earth mining poisoned surrounding farms and nearby villages, causing thousands of people to leave the area.
In 2012, The Guardian described a toxic lake created in conjunction with rare earth mining as "a murky expanse of water, in which no fish or algae can survive. The shore is coated with a black crust, so thick you can walk on it. Into this huge, 10 sq km tailings pond nearby factories discharge water loaded with chemicals used to process the 17 most sought after minerals in the world."
Local residents reported health issues including aching legs, diabetes, osteoporosis and chest problems, The Guardian wrote.
South Africa has also been held up for turning a blind eye to the health impacts of mining.
"The platinum sector in South Africa has been criticized for performing very poorly on human rights — even within the raw materials sector," Müller said.
In 2012, security forces killed 34 miners who had been protesting poor working conditions and low wages at a mine owned by the British company Lonmin. What became known as the "Marikana massacre" triggered several spontaneous strikes across the country's mining sector.
Müller says miners can still face exposure to acid drainage — a frequent byproduct of platinum mining — that can cause chemical burns and severe lung damage. Though this can be prevented by a careful waste system.
Some progress was made in 2016 when the South African government announced plans to make mining companies pay $800 million (€679 million) for recycling acid mine water. But they didn't all comply. In 2020, activists sued Australian-owned mining company Mintails and the government to cover the cost of environmental cleanup.
Another massive issue around mining is water consumption. Since the extraction of critical raw materials is very water intensive, drought prone countries such as South Africa, have witnessed an increase in conflicts over supply.
For years, industry, government and the South African public debated – without a clear agreement – whether companies should get privileged access to water and how much the population may suffer from shortages.
Mining in Brazil: Replacing Nature, People, Land Rights
Beyond the direct health and environmental impact of mining toxic substances, quarrying critical raw materials destroys livelihoods, as developments in Brazil demonstrate.
"Brazil is the major worldwide niobium producer and reserves in [the state of] Minas Gerais would last more than 200 years [at the current rate of demand]," said Juliana Siqueira-Gay, environmental engineer and Ph.D. student at the University of São Paulo.
While the overall number of niobium mining requests is stagnating, the share of claims for Indigenous land has skyrocketed from 3 to 36 percent within one year. If granted, 23 percent of the Amazon forest and the homeland of 222 Indigenous groups could fall victim to deforestation in the name of mining, a study by Siqueira-Gay finds.
In early 2020, Brazilian President Jair Bolsonaro signed a bill which would allow corporations to develop areas populated by Indigenous communities in the future. The law has not yet entered into force, but "this policy could have long-lasting negative effects on Brazil's socio-biodiversity," said Siqueira-Gay.
One example are the niobium reserves in Seis Lagos, in Brazil's northeast, which could be quarried to build electrolytic capacitors for smartphones.
"They overlap the Balaio Indigenous land and it would cause major impacts in Indigenous communities by clearing forests responsible for providing food, raw materials and regulating the local climate," Siqueira-Gay explained.
She says scientific good practice guidelines offer a blueprint for sustainable mining that adheres to human rights and protects forests. Quarries in South America — and especially Brazil — funded by multilaterial banks like the International Finance Corporation of the World Bank Group have to follow these guidelines, Siqueira-Gay said.
They force companies to develop sustainable water supply, minimize acid exposure and re-vegetate mined surfaces. "First, negative impacts must be avoided, then minimized and at last compensated — not the other way around."
Reposted with permission from DW.