Lethal Heating: 12/30/20

30/12/2020

Land Ecosystems Are Becoming Less Efficient At Absorbing CO2

Land ecosystems currently play a key role in mitigating climate change.

The more carbon dioxide (CO₂) plants and trees absorb during photosynthesis, the process they use to make food, the less CO₂ remains trapped in the atmosphere where it can cause temperatures to rise.

But scientists have identified an unsettling trend – as levels of CO₂ in the atmosphere increase, 86 percent of land ecosystems globally are becoming progressively less efficient at absorbing it.

Plants play a key role in mitigating climate change. The more carbon dioxide they absorb during photosynthesis, the less carbon dioxide remains trapped in the atmosphere where it can cause temperatures to rise. But scientists have identified an unsettling trend – 86% of land ecosystems globally are becoming progressively less efficient at absorbing the increasing levels of CO2 from the atmosphere. Credits: NASA's Goddard Space Flight Center/Scientific Visualization Studio/Katy Mersmann

Because CO₂ is a main ‘ingredient’ that plants need to grow, elevated concentrations of it cause an increase in photosynthesis, and consequently, plant growth – a phenomenon aptly referred to as the CO₂fertilization effect, or CFE. CFE is considered a key factor in the response of vegetation to rising atmospheric CO₂ as well as an important mechanism for removing this potent greenhouse gas from our atmosphere – but that may be changing.

For a new study published Dec. 10 in Science, researchers analyzed multiple field, satellite-derived and model-based datasets to better understand what effect increasing levels of CO₂ may be having on CFE. Their findings have important implications for the role plants can be expected to play in offsetting climate change in the years to come.

“In this study, by analyzing the best available long-term data from remote sensing and state-of-the-art land-surface models, we have found that since 1982, the global average CFE has decreased steadily from 21 percent to 12 percent per 100 ppm of CO₂ in the atmosphere,” said Ben Poulter, study co-author and scientist at NASA’s Goddard Space Flight Center. “In other words, terrestrial ecosystems are becoming less reliable as a temporary climate change mitigator.”

What’s Causing It?

Without this feedback between photosynthesis and elevated atmospheric CO₂, Poulter said we would have seen climate change occurring at a much more rapid rate. But scientists have been concerned about how long the CO₂ Fertilization Effect could be sustained before other limitations on plant growth kick in.

For instance, while an abundance of CO₂ won’t limit growth, a lack of water, nutrients, or sunlight – the other necessary components of photosynthesis -- will. To determine why the CFE has been decreasing, the study team took the availability of these other elements into account.

“According to our data, what appears to be happening is that there’s both a moisture limitation as well as a nutrient limitation coming into play,” Poulter said. “In the tropics, there’s often just not enough nitrogen or phosphorus, to sustain photosynthesis, and in the high-latitude temperate and boreal regions, soil moisture is now more limiting than air temperature because of recent warming.”

In effect, climate change is weakening plants’ ability to mitigate further climate change over large areas of the planet.

Next Steps

The international science team found that when remote-sensing observations were taken into account – including vegetation index data from NASA's Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments – the decline in CFE is more substantial than current land-surface models have shown.

Poulter says this is because modelers have struggled to account for nutrient feedbacks and soil moisture limitations – due, in part, to a lack of global observations of them.

“By combining decades of remote sensing data like we have done here, we’re able to see these limitations on plant growth. As such, the study shows a clear way forward for model development, especially with new remote sensing observations of vegetation traits expected in coming years,” he said. “These observations will help advance models to incorporate ecosystem processes, climate and CO₂ feedbacks more realistically.”

The results of the study also highlight the importance of the role of ecosystems in the global carbon cycle. According to Poulter, going forward, the decreasing carbon-uptake efficiency of land ecosystems means we may see the amount of CO₂ remaining in the atmosphere after fossil fuel burning and deforestation start to increase, shrinking the remaining carbon budget.

“What this means is that to avoid 1.5 or 2°C warming and the associated climate impacts, we need to adjust the remaining carbon budget to account for the weakening of the plant CO₂ Fertilization Effect,” he said. “And because of this weakening, land ecosystems will not be as reliable for climate mitigation in the coming decades.”

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(AU) From Bushfires To Flash Flooding, What Will The Australian Summer Of The Future Look Like?

ABC News - Bridget Judd

Residents of Tumbulgum paddle their kayaks down a street on December 15. (AAP: Jason O'Brien)

"State of emergency declared", read the headlines in the days leading up to Christmas last year.

Twelve months on, and some Australian communities once under threat from fire now find themselves grappling with a new emergency as a La Nina weather pattern takes hold.

In parts of northern NSW, where flood warnings were issued this month, consecutive days of wild weather caused thousands of residents to remain on standby for evacuation.

And with the Bureau of Meteorology and the CSIRO's latest biannual report on the climate observing "a more tangible shift in the extremes", questions are emerging about what the summers of the future may hold.

"The idea that we can use the past as a reliable index for the future has sort of been dynamited at the foundations," says David Bowman, a fire ecologist at the University of Tasmania, "because we're seeing such extreme unpredictable things."

'We're talking about really major extremes'

It was around this time last year — just as a series of bushfires that would later be known as Black Summer were beginning to escalate — that Bowman was fielding calls from journalists.

"The year 2020 has been historic in the sense of completely reframing how our modern civilization feels about its place in the environment," he says.

"And certainly the catastrophic bushfires in Australia, and again, in California ... they've all underscored that the earth system is responding to global heating."

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Last summer's fires claimed the lives of 33 people, garnering international headlines and prompting an outpouring of donations and support in the months shortly after. But Bowman believes the coronavirus pandemic "papered over the shock of the bushfires".

Now, as we enter a new summer, "all those anxieties and unfinished business is bubbling up in a way that's different", he says.

"Because during the pandemic — and during winter, strangely — bushfires felt a long way away," he says. "The declaration of a La Nina, I think, was a bit of a false flag game that sort of provided a sense that we were going to be avoiding bushfires."

Bowman points to the K'gari-Fraser Island blaze, which burnt through nearly half the World Heritage-listed site before being contained by heavy rain.

The problem, he says, is "the lining up of the heatwaves and the flooding events".

Water bombers attempting to contain Fraser Island bushfire.

"Unfortunately, what happened in south-east Queensland is that there was this stupendous heatwave that enabled a fire to occur during a La Nina year," he says, adding: "We wouldn't have predicted such an intense fire".

"And now, literally in days, it switched from an uncontrolled bushfire burning Fraser Island to this side of a category one cyclone in southern Queensland and northern New South Wales.

"So ... we're talking about really major extremes."

Could our coastal environment change?

Days of heavy rain and powerful winds in border communities have eroded some of the country's most famous beaches.

Rodger Tomlinson, director of the Griffith Centre for Coastal Management at Griffith University, says areas like Byron Bay — where he has been studying erosion more broadly — were "hit very badly" by the major storm system.

"Generally speaking, if we're going to have more storms, we're going to see more coastal erosion, more rainfall and wet weather, such as we've been seeing," he says.

An erosion-damaged disabled access to Clarkes Beach at Byron Bay. (AAP: Dan Peled)

Asked if today's beaches will be the same in a few decades' time, Tomlinson says there is a risk of change in areas "particularly vulnerable to increased storminess, or if there's no management strategies to keep pace with those events".

"But the general projections in the long-term is that we will see changes to our coastal environments due to climate change," he says.

The key to preserving these coastlines for summers to come, Tomlinson says, will come down to our ability to adapt.

Sea walls are one option, he says — noting that they have been unpopular in the past — as is the long-term possibility communities may need to "be moved away from that erosion".

Storm causes erosion and sea foam at Tugun on the Gold Coast.

"But that's very problematic, and there's no evidence of that being seriously considered anywhere on our coast," he says.

"After the floods in 2011, in the Lockyer Valley, the community of Grantham was relocated to higher ground. But applying that kind of a process on the coast is a lot more difficult, mainly because of the intensity of development in nice locations."

Looking — and planning — ahead

As communities in northern and eastern Australia prepare for a wet summer — vastly different scenes to those witnessed just a year ago — Bowman cautions we are not out of the woods yet.

"What happened on Fraser Island is that the order was wrong. It just got this incredible heatwave, then it got the rain."

Reflecting on the Black Summer bushfires, Bowman believes political leaders need to look beyond simply funding new firefighting equipment, and invest in bushfire mitigation strategies for future.

"Really, where I'm at 12 months on, is not asking 'Was there a royal commission? Was there soul searching? Was there grief and anxiety?" he says.

"All of those things are absolutely true. But what we haven't done is committed to an adaptation pathway."

How to prepare for a flood | Emergency Tips

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From Hopeful To Horrific, Here Are The 10 Most Important Climate Stories Of 2020

Mic - AJ Dellinger

Luis Sinco/Los Angeles Times/Getty Images

For those of us who lived through it, 2020 will forever be remembered as the year that just wouldn't end, the year where it felt like everything bad happened all at once. But it will hopefully also be looked back on by future historians as a turning point in our efforts to address climate change. During a year in which the devastating effects of our changing atmosphere became impossible to ignore, countries and corporations in 2020 seemed to recognize more than ever before that urgent action is necessary.

It will be a few years, or decades, before we know if things really did change for the better in 2020, but regardless of what this year’s ultimate legacy may be, a lot has happened over the last 12 months in the environmental and climate change arenas. This is Mic’s guide to the most important of those happenings.

Wildfires run rampant in Australia and California

Though they started in 2019, Australia’s devastating bush fires raged well into 2020. When the flames finally started to die down in March, the country had lost more than 46 million acres of land, about 6,000 buildings including nearly 3,000 homes, and the lives of 34 people. The fires were particularly damaging to Australia's wildlife. Experts believe as many as one billion animals died in the flames, and many others lost access to the habitats they call home. The fires, exacerbated by record-setting heat plaguing the nation and science-denying politicians who ignored the warning signs, amounted to the worst year for Australia's environment in more than a century.

Matt Mawson/Moment/Getty Images

While it wasn't the literal embers from Australia's fires that carried over to California, it sure felt like a continuation of those destructive flames when the West Coast of the United States was on fire through the summer of 2020. In August, California started experiencing one of its worst wildfire seasons on record. Nearly 10,000 individual fires, including a massive one caused by the use of a pyrotechnic at a gender reveal party, ended up destroying more than four million acres of land. The fires spread into neighboring states, expanding the destruction and forcing hundreds of thousands of people to flee their homes. While pinning the particularly horrific wildfire season on a single cause is difficult, there's little doubt that climate change made matters much worse, and we should likely expect more calamitous events to come.

Joe Biden elected president on climate-forward agenda

NICHOLAS KAMM/AFP/Getty Images

After four years of Donald Trump's seeming disdain for experts and destructive tendencies that left the Environmental Protection Agency in shambles and infused with anti-science impulses, a majority of Americans decided it was time to right the ship. Joe Biden was elected president of the United States, and while he won't take office until 2021, his victory in 2020 was enough to warrant a sigh of relief for many. Biden ran with climate change as one of his top priorities, including a $2 trillion plan to get the US to net-zero carbon emissions by 2050 and a strong history on the issue. He'll have plenty of work ahead of him, as the previous administration left a mess of environmental policy, but with promises to create new positions to address climate change, a climate-focused cabinet, and a slew of executive tools at his disposal, the Biden administration could mark the moment that the US finally gets serious about climate change.

Trump rushes to open up ANWR

Tandem Stills + Motion/Photodisc/Getty Images

After losing the election, Trump has made a point to do as much damage as possible before getting kicked to the curb. Earlier this year, his administration finalized a rule that would allow the federal government to lease land in the Arctic National Wildlife Refuge (ANWR), the largest national wildlife refuge in the country, for oil drilling. To make it happen, Trump is rushing the auction process to try to sell off the land as quickly as possible, just to get the deals on the books before he leaves office. It's one of a number of rush jobs that Trump is trying to push through, as if he's got to fit as many environmental disasters in as possible before January 20, 2021.

Climate pledges get serious

Yaorusheng/Moment/Getty Images

Climate change is real and caused by human activity. Thus far, too much of the emphasis on addressing it has been placed on individuals when the biggest polluters are just a handful of corporations and industrious countries. 2020 is the year that those most responsible for the emissions that are warming the planet finally promised to change their ways. China, the world's leading emitter of greenhouse gases, pledged that it would reach net-zero emissions by 2060. It was joined by gas and oil giants like BP, which claims it will reach net-zero status by 2050. Other companies that present as more climate-conscious, like Microsoft, are making plans to remove their entire history of carbon emissions. Even the US appears to be back on board with addressing the issue, with the incoming Biden administration promising to re-join the Paris Climate Agreement. We just have to hope it isn't too little, too late.

US leaves Paris Agreement (but will be right back)

KENZO TRIBOUILLARD/AFP/Getty Images

2020 marked the five-year anniversary of the Paris Climate Agreement, but the US did not attend the reunion. Under the Trump administration, the US left the accord. It was a promise that Trump made on the campaign trail, set in motion as soon as he took office, and finally made good on this year. Leaving the global agreement didn't tank the effort entirely, though the Paris Climate Agreement has produced considerably less ambitious efforts than are needed. But President-elect Biden has promised to bring the US back into the fold and recommit to the accord, with the goal of leading a much more aggressive effort that other nations will hopefully follow.

Coronavirus-related emissions reductions

NurPhoto/NurPhoto/Getty Images

When the coronavirus pandemic sent much of the world into lockdowns, emissions dropped dramatically. We started to see the skies and water clear up and it seemed as though we might actually put a big enough dent in our emissions to make a difference. That dream was short-lived, as emissions started to skyrocket back to pre-pandemic levels as soon as the world started turning again. The response to the pandemic is not necessarily a blueprint for addressing climate change, but it does show how collective action can make a significant difference. Now we've just got to figure out how to make that action stick.

Another hottest year on record

Jose A. Bernat Bacete/Moment/Getty Images

If it seems like every year is the hottest year in history, that’s because it is. The planet keeps getting warmer, and as a result, we keep setting new records for heat. 2020 is unlikely to be an exception to the rule. Experts indicate that the year is nearly tied for the mark of hottest year in the record books and is likely to earn the title by year's end. This should come as little surprise following the hottest decade in our recorded history and expectations that extreme heat will continue to get worse throughout this century.

Clean energy gains momentum

kamisoka/E+/Getty Images

While the Trump administration has done its damnedest to prop up coal and oil, 2020 has been a pretty momentous year for renewable energy alternatives. For the first time ever, clean energy sources like wind and solar surpassed coal as an energy source in the US, even as Trump held back funding and tried to hide studies supporting clean innovations. Add to that the fact that clean energy has become cheaper and more sustainable than some dirty-burning fuels and has made significant strides in countries like the UK, and it looks like the world finally may be embracing renewable energy in a meaningful way.

Arctic and Antarctic ice disappearing at an alarming rate

Anton Petrus/Moment/Getty Images

Much of the planet is warming, and the Arctic is no exception. The polar region known for its thick layers of sea ice has been feeling the effects of climate change, and we started to learn just how bad it is getting this year. Researchers discovered that the Arctic is warmer than it has been at any point in the last three million years. That perhaps shouldn't come as a surprise, as even the coldest spot on the planet started to feel the heat this year, but the effects are potentially devastating. Ice around the planet is melting at what experts have called a "mind-blowing" rate, which could expose the planet to all sorts of harmful effects, from rising oceans to exposure to previously frozen viruses and diseases.

Public opinion polls showing people are finally starting to care about climate crisis

NurPhoto/NurPhoto/Getty Images

If there is one good thing to come out of all the environmental disasters that have plagued the planet throughout 2020 and the years prior, it's the fact that the general public finally seems to be prioritizing the planet. This year saw more support for truly taking action to address climate change. Polling found that two-thirds of Americans believe the government is doing too little to address the climate crisis and nearly three in four believe that climate change is happening. That includes newfound support from young Republicans, who are bucking the party and pushing for action on climate change. It appears environmental disasters are one issue that can cut through the partisan bullshit that has clouded the climate conversation for decades, as many are faced to look toward an ugly future if no action is taken.

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