Lethal Heating: 08/22/20

22/08/2020

Greenland's Ice Sheet Melted Away At Record Levels In 2019, Scientists Fear It Will Continue

ABC News - Reuters

Greenland's ice sheet melted away at record levels during 2019. (Woods Hole Oceanographic Institution: Matt Osman)

Key Points

Greenland lost 532 gigatonnes of ice, 15 per cent more than the previous record in 2012

Its icy bulk melted more quickly than anticipated amid climate warming

Another study indicated Greenland is no longer getting enough annual snowfall to replace ice loss

Greenland's ice sheet lost a record amount of mass in 2019, a finding that could prompt scientists to redefine their worst-case scenario as they assess the effects of climate change.

Geoscientist and glaciologist Ingo Sasgen of the Alfred Wegener Institute in Germany said that the rate of ice loss — which had slowed in the previous two-year period — increased again as warm air flowed northward from lower latitudes, leading to the island experiencing a record loss in its ice mass.

That loss of 532 gigatonnes of ice — equivalent to about 66 tonnes of ice for each person on Earth — was 15 per cent more than the previous record in 2012.

Greenland's ice melt is of particular concern, as the ancient ice sheet holds enough water to raise sea levels by at least 6 metres if it were to melt away entirely.

The study added to evidence that Greenland's icy bulk has been melting more quickly than anticipated due to global warming.

Another study last week indicated the island was no longer getting enough annual snowfall to replace ice lost to melting and calving at the edges of glaciers.

Greenland's ice sheet holds enough water to raise sea levels by at least 6 metres if it melts away entirely. (AP: Danmarks Meteorologiske Institut/Steffen M Olsen)

"We are likely on the path of accelerated sea level rise," Dr Sasgen said.

"More melting of the ice sheet is not compensated by periods when we have extreme snowfall."

The study, published in the journal Communications Earth & Environment, used data collected by satellites to the gravitational force of the ice mass, which scientists can use to calculate how much snow and ice is locked within.

A 'depressing' new record

Other research has shown the melting is being helped by water pooling atop the ice and at meltwater streaming between the ice sheet and the bedrock.

These studies have helped scientists refine their projections of how climate change will impact the Arctic, and how quickly.

Dr Sasgen compared the sobering process to getting difficult news from a doctor.

"It's always depressing to see a new record," he said.

He says the studies offer insight into "where the problem is, and you also know to some extent what the treatment is."

"It is hard to tell if these [weather] patterns will be the new normal, and which pattern will occur with which frequency."

The Arctic already has been warming at least twice as quickly as the rest of the world for the past 30 years, as the amount of greenhouse gases accumulated in the atmosphere continues to rise.

That warming has also affected the Arctic sea ice, which shrank to its lowest level since figures were originally recorded 40 years ago.

The Greenland ice sheet is up to 3 kilometres thick in places

In terms of Greenland's fate, "I would argue that we've been in a new normal for the past couple decades of accelerating mass loss," glaciologist at the NASA Goddard Space Flight Centre, Laura Andrews said.

"Greenland is going to continue to lose mass."

If the rate of ice loss experienced in 2019 were to continue, the annual impact on sea levels could cause increasing coastal flooding that affects up to 30 million more people each year by the end of the century, said Andrew Shepherd, a polar scientist at University of Leeds.

The new findings underline that "we need to prepare for an extra 10 centimetres of global sea level rise by 2100 from Greenland alone," Mr Shepherd said.

"We have to invent a new worst-case climate warming scenario, because Greenland is already tracking the current one."

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(AU) Dishing The Dirt: Australia’s Move To Store Carbon In Soil Is A Problem For Tackling Climate Change

The Conversation - Robert Edwin White | Brian Davidson

Shutterstock

Authors

Robert Edwin White is Professor Emeritus, University of Melbourne
Brian Davidson is Senior Lecturer, Department of Agriculture and Food Systems, University of Melbourne

To slow climate change, humanity has two main options: reduce greenhouse gas emissions directly or find ways to remove them from the atmosphere.

On the latter, storing carbon in soil – or carbon farming – is often touted as a promising way to offset emissions from other sources such as energy generation, industry and transport.

The Morrison government’s Technology Investment Roadmap, now open for public comment, identifies soil carbon as a potential way to reduce emissions from agriculture and to offset other emissions.

In particular, it points to so-called “biochar” – plant material transformed into carbon-rich charcoal then applied to soil.

But the government’s plan contains misconceptions about both biochar, and the general effectiveness of soil carbon as an emissions reduction strategy.

Soil carbon storage is touted as a way to offset emissions from industry and elsewhere. Shutterstock

What is biochar?

Through photosynthesis, plants turn carbon dioxide (CO₂) into organic material known as biomass. When that biomass decomposes in soil, CO₂ is produced and mostly ends up in the atmosphere.

This is a natural process. But if we can intervene by using technology to keep carbon in the soil rather than in the atmosphere, in theory that will help mitigate climate change. That’s where biochar comes in.

Making biochar involves heating waste organic materials in a reduced-oxygen environment to create a charcoal-like product – a process called “pyrolysis”. The carbon from the biomass is stored in the charcoal, which is very stable and does not decompose for decades.

Plant materials are the predominant material or “feedstock” used to make biochar, but livestock manure can also be used. The biochar is applied to the soil, purportedly to boost soil fertility and productivity. This has been tested on grassland, cropping soils and in vineyards.

Biochar is produced by burning organic material in a low oxygen environment. Shutterstock

But there’s a catch

So far, so good. But there are a few downsides to consider.

First, the pyrolysis process produces combustible gases and uses energy – to the extent that when all energy inputs and outputs are considered in a life cycle analysis, the net energy balance can be negative. In other words, the process can create more greenhouse gas emissions than it saves. The balance depends on many factors including the type and condition of the feedstock and the rate and temperature of pyrolysis.

Second, while biochar may improve the soil carbon status at a new site, the sites from which the carbon residues are removed, such as farmers’ fields or harvested forests, will be depleted of soil carbon and associated nutrients. Hence there may be no overall gain in soil fertility.

Third, the government roadmap claims increasing soil carbon can reduce emissions from livestock farming while increasing productivity. Theoretically, increased soil carbon should lead to better pasture growth. But the most efficient way for farmers to take advantage of the growth, and increase productivity, is to keep more livestock per hectare.

Livestock such as cows and sheep produce methane – a much more potent greenhouse gas than carbon dioxide. Our analysis suggests the methane produced by the extra stock would exceed the offsetting effect of storing more soil carbon. This would lead to a net increase, not decrease, in greenhouse gas

Farmers would have to increase stock numbers to benefit from pasture growth. Dan Peled/AAP

A policy failure

The government plan refers to the potential to build on the success of the Emissions Reduction Fund. Among other measures, the fund pays landholders to increase the amount of carbon stored in soil through carbon credits issued through the Carbon Farming Initiative.

However since 2014, the Emissions Reduction Fund has not significantly reduced Australia’s greenhouse gas emissions – and agriculture’s contribution has been smaller still.

So far, the agriculture sector has been contracted to provide about 9.5% of the overall abatement, or about 18.3 million tonnes. To date, it’s supplied only 1.54 million tonnes – 8.4% of the sector’s commitment.

The initiative has largely failed because several factors have made it uneconomic for farmers to take part. They include:

overly complex regulations
requirements for expensive soil sampling and analysis
the low value of carbon credits (averaging $12 per tonne of CO₂-equivalent since the scheme began).

For many farmers, taking part in the Emissions Reduction Fund is uneconomic. Shutterstock

A misguided strategy

We believe the government is misguided in considering soil carbon as an emissions reduction technology.

Certainly, increasing soil carbon at one location can boost soil fertility and potentially productivity, but these are largely private landholder benefits – paid for by taxpayers in the form of carbon credits.

If emissions reduction is seen as a public benefit, then the payment to farmers becomes a subsidy. But it’s highly questionable whether the public benefit (in the form of reduced emissions) is worth the cost. The government has not yet done this analysis.

To be effective, future emissions technology in Australia should focus on improving energy efficiency in industry, the residential sector and transport, where big gains are to be made.

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New Model For Pricing Carbon Will Help Meet Net-Zero Climate Change Goals

Phys.org - Columbia University

Credit: Unsplash/CC0 Public Domain

An article released today by researchers at Columbia University's Center on Global Energy Policy in the journal Nature Climate Change introduces a new approach for pricing carbon—Near-term to Net Zero.

As policymakers and advocates increasingly focus on net-zero emissions by midcentury, the Near-term to Net Zero approach is a method of setting carbon prices that could ensure net-zero emissions goals are met as one piece of comprehensive climate policies.

A carbon price is a fee on carbon dioxide released into the atmosphere that is unique in encouraging emissions reductions wherever and however they can be achieved at a low cost. How much to charge for each ton of emissions is perhaps the most crucial element of a carbon pricing policy.

Economists have long focused on the social cost of carbon to calculate "correct" carbon prices because, in theory, it balances the benefits and costs of emissions reductions. The article highlights how the social cost of carbon, however, cannot be estimated with sufficient precision to provide any practical value to policymakers setting carbon prices.

The Near-term to Net Zero approach estimates the carbon prices needed for consistency with a pathway to a net-zero emissions target, or the point where the overall balance between emissions produced and emissions taken out of the atmosphere equals zero. It uses the reliable information we have now and avoids the uncertainties of long-term changes we can't predict.

"The social cost of carbon is a useful concept, but the risks of climate change are far too complex for credible comprehensive damage estimates," said lead author Noah Kaufman, a research scholar at the Center on Global Energy Policy. "Near-term to Net Zero enables policymakers to use both climate science and economics to chart an effective and efficient pathway to net-zero emissions."

By pairing a net-zero emissions target with policies that can rapidly reduce emissions right away, the Near-term to Net Zero approach aligns with current climate policy discussions in the United States and the world. Carbon pricing developed using the Near-term to Net Zero approach complements the investments and other policy tools needed to constrain global warming from rising beyond dangerous levels, said Kaufman.

The article provides illustrative estimates for Near-term to Net Zero carbon prices for the United States assuming three possible net-zero targets: 2040, 2050, and 2060. The energy model GCAM-U.S. is used to estimate carbon prices over the next 10 years needed to follow a straight line pathway to those goals, assuming that the carbon price is combined with complementary policies that address separate market failures: energy-efficiency policies, air-pollution regulations, and early-stage support for the deployment of low-carbon technologies.

Near-term to Net Zero carbon prices in 2025, are $32, $52 and $93 per metric ton (in 2018 dollars) for net-zero targets in 2060, 2050, and 2040, respectively.

"There's no debate about the fact that climate change is happening now, and reducing our contribution to a warming planet is critical to our efforts to avoid the worst impacts of climate change," said Jason Bordoff, professor of practice in Columbia's School of International and Public Affairs, and founding director of the Center on Global Energy Policy.

"This important research gives us another tool in the toolbox to figure out how we can get to net-zero as quickly as possible, and no later than 2050, by setting a price on carbon that, along with complementary policies, discourages continued pollution and creates incentives for innovation to deliver the clean energy the world needs."

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