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Fastest Shrinking Greenland Glacier Growing Again: NASA

"That was kind of a surprise. We kind of got used to a runaway system," said Geological Survey of Denmark and Greenland ice and climate scientist Jason Box

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greenland, glacier
This 2016 photo provided by NASA shows patches of bare land at the Jakobshavn glacier in Greenland. The major Greenland glacier that was one of the fastest shrinking ice and snow masses on Earth is growing again, a new NASA study finds. VOA

A major Greenland glacier that was one of the fastest shrinking ice and snow masses on Earth is growing again, a new NASA study finds.

The Jakobshavn (YA-cob-shawv-en) glacier around 2012 was retreating about 1.8 miles (3 kilometers) and thinning nearly 130 feet (almost 40 meters) annually. But it started growing again at about the same rate in the past two years, according to a study in Monday’s Nature Geoscience . Study authors and outside scientists think this is temporary.

“That was kind of a surprise. We kind of got used to a runaway system,” said Geological Survey of Denmark and Greenland ice and climate scientist Jason Box. “The good news is that it’s a reminder that it’s not necessarily going that fast. But it is going.”

Box, who wasn’t part of the study, said Jakobshavn is “arguably the most important Greenland glacier because it discharges the most ice in the northern hemisphere. For all of Greenland, it is king.”

glacier, greenland
“The good news is that it’s a reminder that it’s not necessarily going that fast. But it is going.” VOA

Cyclical cooling

A natural cyclical cooling of North Atlantic waters likely caused the glacier to reverse course, said study lead author Ala Khazendar, a NASA glaciologist on the Oceans Melting Greenland (OMG) project. Khazendar and colleagues say this coincides with a flip of the North Atlantic Oscillation — a natural and temporary cooling and warming of parts of the ocean that is like a distant cousin to El Nino in the Pacific.

The water in Disko Bay, where Jakobshavn hits the ocean, is about 3.6 degrees cooler (2 degrees Celsius) than a few years ago, study authors said.

While this is “good news” on a temporary basis, this is bad news on the long term because it tells scientists that ocean temperature is a bigger player in glacier retreats and advances than previously thought, said NASA climate scientist Josh Willis, a study co-author. Over the decades the water has been and will be warming from man-made climate change, he said, noting that about 90 percent of the heat trapped by greenhouse gases goes into the oceans.

“In the long run we’ll probably have to raise our predictions of sea level rise again,” Willis said.

glacier, greenland
Think of the ocean temperatures near Greenland like an escalator that’s rising slowly from global warming, Khazendar said. VOA

Like an escalator

Think of the ocean temperatures near Greenland like an escalator that’s rising slowly from global warming, Khazendar said. But the natural North Atlantic Oscillation sometimes is like jumping down a few steps or jumping up a few steps. The water can get cooler and have effects, but in the long run it is getting warmer and the melting will be worse, he said.

ALSO READ: Due to Global Warming Mount Everest Melting Glaciers Throw Up Climbers’ Bodies

Four outside scientists said the study and results make sense.

University of Washington ice scientist Ian Joughin, who wasn’t part of the study and predicted such a change seven years ago, said it would be a “grave mistake” to interpret the latest data as contradicting climate change science.

What’s happening, Joughin said, is “to a large extent, a temporary blip. Downturns do occur in the stock market, but overall the long term trajectory is up. This is really the same thing.” (VOA)

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Here’s how Carbon Footprint Can be Reduced in India

Carbon footprint in India can be reduced by 20%

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Carbon global warming

BY VISHAL GULATI

The report focuses on the potential to reduce greenhouse gas emissions from the two most carbon-intensive products — passenger cars and residential buildings.

Producing and using materials more efficiently to build passenger cars and residential homes could cut carbon dioxide (CO2) equivalent emissions between 2016 and 2060 by up to 25 gigaton across the Group of Seven (G7) member states, the International Resource Panel (IRP) finds in a summary for policymakers released here on Wednesday.

This is more than double the annual emissions from all the world’s coal-fuelled power plants.

The IRP finds that emissions from the production of materials like metals, wood, minerals and plastics more than doubled over the 20-year period to 2015, accounting for almost one-quarter of all greenhouse gas emissions.

Carbon products cars
Majority of carbon-intensive products are used in manufacturing cars. Pixabay

It warns that without boosting material efficiency, it will be almost impossible and substantially more expensive to keep global heating below 1.5 degrees Celsius — the more ambitious of the two Paris climate targets.

The IRP Summary for Policymakers, Resource Efficiency and Climate Change: Material Efficiency Strategies for a Low-Carbon Future, prepared at the request of the G7, is the first comprehensive scientific analysis estimating total cuts in greenhouse gas emissions in homes and cars that can be achieved through material efficiency.

Together, the construction and manufacturing sectors are responsible for an estimated 80 per cent of emissions generated by the first use of materials.

Using strategies and technologies that already exist, G7 countries could save up to 170 million tons of carbon emissions from residential homes in 2050.

India could save 270 million tons, and China could save 350 million tons in 2050 in this same sector.

If we look at the full lifecycle of cars, material efficiency strategies could help G7 countries, China and India reduce GHG emissions by up to 450 million tons each in 2050. These reductions can help countries stay within their carbon budget.

Extending the lifetime of products, reusing components, substituting or using less material, and making more intensive use of materials by, for example, ride-sharing, are all strategies that G7 countries could implement today to tackle global warming.

“Climate mitigation efforts have traditionally focused on enhancing energy efficiency and accelerating the transition to renewables. While this is still key, this report shows that material efficiency can also deliver big gains,” UN Environment Executive Director Inger Andersen said.

The IRP finds that the carbon footprint of the production of materials for cars could be cut by up to 70 per cent in G7 countries, and 60 per cent in China and 50 per cent in India in 2050.

The largest emission savings from passenger vehicles come from a change in how people use cars, like car-pooling and car-sharing, and a move away from large SUVs.

Greenhouse gases carbon
The construction and manufacturing sectors are responsible for an estimated 80 per cent of emissions generated by the first use of materials. Pixabay

The report also shows that greenhouse gas emissions from the production of materials for residential buildings in the G7, China and India could be reduced between 50 and 80 per cent in 2050 with greater material efficiency.

The most promising strategies include more intensive use of space e.g. reducing demand for floor space, switching out concrete and masonry for sustainably produced wood, improving recycling, and building lighter homes using less carbon-intensive steel, cement and glass.

Reducing demand for floor space in the G7 by up to 20 per cent could lower greenhouse gas emissions from the production of materials by up to 73 per cent in 2050.

Shared homes, smaller units, and downsizing when children move out lead to these big reductions.

The cuts revealed by the report are on top of emission savings generated by the decarbonisation of electricity supply, the electrification of home energy use, and the shift towards electric and hybrid vehicles.

Many of these emission reductions will only be possible if countries create enabling policy environments and incentives, the report says.

UN Secretary-General Antonio Gutteres wants countries to increase the ambition of their climate targets at the ongoing UN climate change negotiations (COP25) that entered its final stage in this Spanish capital.

Also Read- 86 Fashion Companies Partner with Political Leaders to Deliver Climate Action

The IRP report urges policymakers to integrate material efficiency into their Nationally Determined Contributions (NDCs) to set higher emission reduction targets that will limit the damage from global warming.

Currently, only Japan, India, China, and Turkey mention resource efficiency, resources management, material efficiency, circular economy or consumption side instruments as explicit mitigation measures in their NDCs. (IANS)