31/12/2020

This Year Was A Disaster For The Planet

Huffington Post - Sarah Ruiz-Grossman

From record-breaking bushfires to devastating hurricanes, human-driven climate change keeps killing us.

A bushfire burns in Bodalla, New South Wales, Australia, Saturday, January 25,
A bushfire burns in Bodalla, New South Wales, Australia, Saturday, January 25, 2020. AP Photo/Noah Berge
The climate is changing, its effects are deadly, and it’s getting worse every year. 

Even as global carbon emissions were expected to decrease by about 7% this year due to coronavirus restrictions on normal activities, this has only “briefly slowed ― but far from eliminated ― the historic and ever-increasing burden of human activity on the Earth’s climate,” United Nations environmental researchers wrote in a December report.

This year has seen record-breaking heat, bushfires and storms. U.N. Secretary-General António Guterres urged every country to declare a “climate emergency.”

Throughout President Donald Trump’s time in office, his administration rolled back environmental protections around clean water, auto emissions and more.

It remains to be seen what President-elect Joe Biden will do to curb the nation’s impact on the global climate, but he and Vice President-elect Kamala Harris have named climate change as a top priority, including a commitment to rejoin the Paris climate accord that Trump pulled the US out of.

Here are some of the ways climate change has wreaked havoc on Earth’s inhabitants this year.

Flames rise near homes during the Blue Ridge fire on Oct. 27 in Chino Hills,
Flames rise near homes during the Blue Ridge fire on Oct. 27 in Chino Hills, California. David McNew via Getty Images

Historic fires

Australia has faced the cost of a devastating and lengthy bushfire season that burned nearly 12 million hectares of bushland, killing 33 people and an estimated 1 billion native animals.

Dubbed a “black summer” by Prime Minister Scott Morrison, the unusually prolonged and intense bushfires have increased pressure on the government to reduce greenhouse gas emissions.

Scientists have warned that increased temperatures and heatwaves will lead to more dangerous fire seasons and severe weather events, while shorter winters will reduce the window for hazard reduction to mitigate the impact of fires.

This year was also a record-breaker for fires in California — again. As of last year, four of the five largest wildfires in the fire-prone state had happened this decade alone.

This year, four of the five largest wildfires in state history happened this year alone.

Wildfires have been worsening in California, with hotter temperatures and dry conditions often combining with high winds to create a longer, more destructive fire season.

Scientists have linked the worsening fires across the Western U.S. to climate change.

Some regions are being ravaged over and over, year after year, such as Northern California’s wine country, which was hit by deadly fires in 2017 only to be the site of the fifth-biggest fire in state history this year, spurring mass evacuations.

In August, the North Complex fire killed 15 people in Butte County — the same county as 2018’s Camp fire, which killed 85 people and burned down nearly the entire town of Paradise.

“CLIMATE. CHANGE. IS. REAL,” tweeted California Gov. Gavin Newsom in September, as fires across the state burned millions of acres, a record-breaking heat wave engulfed Southern California, and broad swaths of the state were blanketed with unhealthy levels of smoke.

A man with an umbrella for shade walks past the thermometer at Calvary Church in Woodland Hills, California,...
A man with an umbrella for shade walks past the thermometer at Calvary Church in Woodland Hills, California, as it registers 116 degrees Fahrenheit on Aug. 19. Al Seib via Getty Images
Record-breaking heat 

This year is on track to be one of the two hottest ever on record. The planet had its hottest September and its second hottest July and November ever, according to the National Oceanic and Atmospheric Administration.

This August — the third hottest August in the nation’s history — Phoenix saw average temperatures of 99 degrees. And in California, a record-breaking heat wave over Labor Day weekend brought Los Angeles County its highest temperature ever, 121 degrees.

Globally, the past five years have been the Earth’s hottest in recorded history, with 2016 the hottest ever, followed by 2019, 2017, 2015 and 2018. It remains to be seen if 2020 will usurp 2016 as the hottest year ever, or come in second place.

These recent peak temperatures follow decades of warming around the globe, largely caused by human-made emissions. Higher temperatures are linked to a range of dangerous natural disasters including extreme floods, hurricanes, wildfires ― and deaths.

Meanwhile Australian summers are now effectively twice as long as its winters as climate change has increased temperatures since the middle of the last century, research released in the wake of the nation’s unprecedented fire season showed in March.

The report by the Australia Institute, a Canberra-based think tank, compared data from the past two decades with mid-20th century benchmarks of temperatures at the calendar start of seasons in temperate and sub-tropical parts of the country.

Over the last two decades, summer across most of Australia has been on average one month longer than half a century ago, while winter has contracted by an average three weeks.

Over the past five years, the analysis showed, Australian summers were on average 50% longer than they were in the mid-twentieth century based on temperature readings.

“Our findings are not a projection of what we may see in the future,” said Richie Merzian, climate and energy program director at the Australia Institute. “It’s happening right now.”

A family walks amid destruction on Nov. 22 in Providencia, Colombia, which was hit by Hurricane Iota...
A family walks amid destruction on Nov. 22 in Providencia, Colombia, which was hit by Hurricane Iota as a Category 5 storm, the strongest on record to affect the country. Getty Images via Getty Images
Deadly storms

The 2020 storm season was the most active on record. Subtropical storm Theta in November was the 29th named storm of the Atlantic season— breaking the record for the highest number of storms in a year. For only the second time in history, the predetermined list of 21 storm names ran out, leading scientists to use the Greek alphabet to name subsequent storms.

Several of this year’s hurricanes and tropical storms were deadly, including tropical storm Isaias, which ravaged the East Coast in August, Hurricane Delta, which tore through the mid-Atlantic in October, and Hurricane Zeta, which destroyed homes across the Southeast US later that month and left over a million people without power.

Hurricane Laura, which made landfall in Louisiana in August, killed over a dozen people and carried with it 150-mph winds, tying an 1856 hurricane for the strongest to make landfall in the state.

Sea ice coverage in September 2020. The purple line indicates the previous median ice coverage extent from 1981-2010. National Snow and Ice Data Center, University of Colorado, Boulder
Devastating back-to-back hurricanes, Eta and Iota, slammed Central America in November, leading to dozens dying in mudslides in Guatemala, tens of thousands of homes being destroyed across the region, and half a million people being displaced from their homes.

And Typhoon Vamco, which hit the Philippines in November, killed dozens of people, submerged villages and cut power to millions.

Scientists have found that climate change has likely increased the intensity of hurricanes.

A study published in the journal Nature in November found that in recent decades, hurricanes have increasingly stayed more intense for longer periods, brining higher winds and more flood damage inland as they’ve gathered more moisture from warming oceans.

Dramatic loss of sea ice

This year, the Arctic’s sea ice cover shrank to its second lowest levels since records started being kept in the late 1970s, according to NASA.

The 14 smallest ice coverage extents for the region have all occurred in the last 14 years, per the NOAA.

The amount of Arctic sea ice coverage each October has declined about 10% per decade — losing an area about the size of South Carolina each year, according to the National Snow and Ice Data Center.

Sea ice, or frozen ocean water, is “a critical component of our planet because it influences climate,” according to the center. As rising temperatures melt broad swaths of sea ice over time, there are fewer white surfaces to reflect the sunlight and more heat is absorbed at the Earth’s surface, leading to temperatures rising even further in a vicious cycle.

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The World’s 10 Most Destructive Climate Disasters Of 2020

NEWS.com.au - Charis Chang

Locust swarms, wind storms and Australia’s bushfires have been included in a list of the world’s 10 most damaging climate disasters.



A new report from CSIRO and BOM has warned us about the worsening effects of climate change. Australia’s devastating Black Summer bushfires have been included in a list of the world’s most expensive disasters.

A new report by Christian Aid, Counting the cost 2020: a year of climate breakdown identifies 15 of the most destructive climate disasters of the year.

Nine of these events have caused damage worth at least $5 billion each and this includes Australia’s bushfires.

The report notes that financial costs are usually higher in more wealthy countries because they have more valuable property but despite this some poorer countries are still featured in the top 10.

South Sudan, for example, experienced one of its worst floods on record, which killed 138 people and destroyed the year’s crops.

Six of the 10 most costly events took place in Asia, and five of them were associated with an unusually rainy monsoon.

Some events unfolded over months, including the floods in China and India, which had an estimated cost of $32 billion and $10 billion respectively.

A boy and a man save chairs from a flooded house due to the heavy rains caused by Hurricane Eta in Puerto Barrios. Picture: Johan Ordonez/AFP

There were also smaller disasters including a heatwave in the Russian territory of Siberia, floods in South Sudan, fires in South America, typhoons in Philippines and floods in Vietnam.

“Whether it be floods in Asia, locusts in Africa or storms in Europe and the Americas, climate change has continued to rage in 2020,” report author Dr Kat Kramer and Christian Aid climate policy lead said.   

“It is vital that 2021 ushers in a new era of activity to turn this tide.”

University of Melbourne climate science lecturer Dr Andrew King said there was evidence that human-caused climate change had contributed to the severity of some severe weather events, particularly heatwaves and wildfires.

“Within this challenging landscape there is an opportunity to change direction and work towards a greener future, so we can limit global warming in line with the Paris Agreement, and avoid some of the most damaging consequences of climate change that we project under continued high greenhouse gas emissions.”

1. HURRICANES, UNITED STATES

This year’s Atlantic hurricane season was record-breaking, with 30 named storms that caused at least 400 deaths, at a combined cost of $US41 billion.

Hurricane Eta, which was one of nine storms named from Greek alphabet after other names were exhausted, killed 153 people in Central America, most of them in Honduras and Guatemala.

Firemen rescue local residents after the overflowing of the Ulua River due to Hurricane Eta November 5, 2020. Picture: Orlando Sierra/AFP
In the US, hurricanes Laura and Sally caused the most damage. Both of them affected the state of Louisiana, which was struck by five named storms throughout the season, setting a new record. Many of those storms made landfall only a few weeks apart.

There has been an increase in the number of named storms in the Atlantic basin since 1980 and at least nine of the storms this year experienced “rapid intensification”, a phenomenon by which tropical cyclones acquire high wind speeds in a short period of time.

Estimated cost: $US41 billion

2. FLOODS, CHINA

China experienced intense floods starting in June that impacted more than 35 million people, and left at least 278 dead or missing.

Some of the most affected areas were around the densely populated Yangtze river basin, including the provinces of Sichuan and Guizhou, and the city of Chongqing, where more than 30 million people live.

There are projections that climate change will see a higher proportion of the country’s rain falling as concentrated downpours, with a 2016 study finding that China was the country with the highest risk of floods in the world.

Estimated cost: $US32 billion

Submerged streets and buildings after heavy rain caused flooding in Yangshuo, in China's southern Guangxi region in June. Picture: STR/AFP/China OUT
3. FIRES, UNITED STATES

The 2020 fire season between July and November on the west coast of the US was one of the most destructive on record.

Dozens of wildfires across California, Colorado, Arizona, Washington and Oregon burned more than eight million acres of land.

About half of the burnt area is within the borders of California, setting a new record for the state. At least 42 people were killed.

The smoke from the fires, containing dangerous particulate matter and ozone, caused a surge in hospital admissions in the region. It also affected neighbouring states and Canada.

Temperatures in the region have been increasing over the last century and in August, when the fires were at their most intense, the region was experiencing a record-breaking heatwave.

In Death Valley, a temperature of 54.4C was recorded – provisionally the hottest temperature ever on record.

Estimated cost: $US20 billion

A firefighter douses flames as they push towards homes in California on September 7. The fire was triggered by a firework at a gender reveal party. Picture: Josh Edelson/AFP

4. CYCLONE AMPHAN, BAY OF BENGAL

With sustained wind speeds of 270km/h, Cyclone Amphan was one of the strongest storms on record in the Bay of Bengal, India, and also the most costly this year.

At least 128 people were killed and the cyclone also caused great damage in cities like Bangladesh, Sri Lanka and Bhutan.

Some studies have found the strength of cyclones affecting the countries bordering the North Indian Ocean has been increasing.

A warmer atmosphere can also drive more extreme rainfall during cyclones that increase the threat of flooding.

Global sea levels have already increased about 23cm and this has dramatically increased the distance that storm surges can reach.

India, which is currently the largest emitter of greenhouse gases in the world, is one of the few countries that has set targets to reduce carbon emissions that are “compatible” with keeping the planet’s temperature increase below 2C compared to pre-industrial times, according to Climate Action Tracker.

Estimated cost: $US13 billion

Submerged vehicles in a flooded alleyway after the landfall of Cyclone Amphan in Kolkata. Picture: Satyaki Sanyal/AFP
5. FLOODS, INDIA

The monsoon season brought extreme rainfall to India this year, causing floods and landslides that caused at least 2,067 deaths between June and October.

In Kerala, a single landslide in a tea plantation killed 49 people, and in Assam, the floods affected more than 60,000 between May and October, with 149 deaths.

The city of Hyderabad, where almost 10 million people live, saw a record rainfall of 29.8cm in 24 hours – almost 6cm more than the previous record. The floods submerged cars and houses, killing at least 50 people.

This is the second consecutive year where India experienced abnormally high rainfalls during the monsoon season.

Over the last 65 years, the country has seen a three-fold increase in extreme rain events.

Estimated cost: $US10 billion

Villagers travel on a boat at the flood affected area of Gagalmari village in Morigaon district of Assam state on July 14. Picture: Biju Boro/AFP

6. LOCUST SWARMS, EAST AFRICA

During the first few months of 2020, many countries in East Africa such as Eritrea, Ethiopia, Kenya, Somalia and Uganda, experienced a locust invasion following an unusual rainy season at the end of 2019.

The locust swarms attacked vast areas of the region, destroying crops, trees and pastures.

According to the UN Food and Agriculture Organisation (FAO), this was the worst outbreak in 25 years for the Horn of Africa and in 70 years for Kenya.

The World Bank estimated losses could amount to $US8.5 billion due to crop losses and other “economic, human, and environmental impacts”.

Scientists predict that the conditions for more flooding, cyclones and pests could be more frequent as the planet warms.

Estimated cost: $US8.5 billion

Swarms of grasshoppers are seen over the agricultural fields in Jigiiga capital of Somali region, Ethiopia on October 31. Picture: Minasse Wondimu Hailu/Anadolu Agency via Getty Images

7. FLOODS, JAPAN

Extreme rains in July on the island of Kyushu during the region’s rainy season, caused 82 fatalities.

The record-breaking intensity of the rains caused floods and landslides, with more than 250,000 people having to be evacuated. At least 14 people were killed when a care home was flooded.

In some parts of the island, rainfall exceeded 410mm in 24 hours.

Several cities, such as Kuma and Kanoya, saw record downpours, exceeding 80 and 100mm of rain in just one hour, respectively.

Japan’s rainfall pattern has been changing over the last decades, according to a recent report by Japan’s Meteorological Agency.

There are now more days with heavy rain and fewer days with light rain. Extreme downpours are becoming more common.

Estimated cost: $US 8.5 billion

A village lies in ruins after being flooded by the nearby Kuma River following torrential rain, on July 8, 2020 in Kuma, Japan. Picture: Carl Court/Getty Images



An officer walks past a damaged car in Hitoyoshi, in Kumamoto Prefecture on July 8, 2020. Picture: STR/JIJI PRESS/AFP
8. WIND STORMS, EUROPE

Europe was hit by several windstorms (or extratropical cyclones) in February and October. The two with the highest costs were Ciara and Alex, whose combined damage amounts to more than $US5.9 billion.

Ciara hit the UK and Ireland in early February, continuing to move east over several weeks. It caused 14 fatalities in eight countries and had an estimated cost of $US2.7 billion.

Floods caused by Alex in France and Italy killed 16 people in October and destroyed about $US3.2 billion in infrastructure.

The Italian region of Piedmont experienced its highest rainfall since 1958, with one station recording 630mm of rain in 24 hours.

Estimated cost: $US5.9 billion

The Welsh village of Crickhowell was cut off as the river Usk burst its banks on February 16. Picture: Christopher Furlong/Getty Images





Rescue workers help two people to leave their flooded home on February 17 in Hereford, England. Picture: Christopher Furlong/Getty Images

9. BUSHFIRES, AUSTRALIA

The Black Summer bushfires began at the end of 2019 and destroyed between 24 to 40 million hectares of bushland, destroying buildings, killing more than a billion wild animals and causing at least 34 deaths.

Smoke blanketed the country’s biggest cities including Sydney and Canberra and the report said the cost of smoke-related deaths alone was estimated at $1.4 billion.

Insured costs have been estimated at $US3.6 billion, although other estimates have put the total costs as high as $100 billion (US$70 billion).

Estimated damage: $US5 billion

The Sydney Opera House is seen through smoke haze from bushfires in Sydney on January 8. Picture: Steven Saphore/AAP
10. FLOODS, PAKISTAN

Heavy rains during the monsoon caused 410 deaths in Pakistan and saw floods and landslides cause an estimated $US1.5 billion in damage.

In the Sindh province, extreme rainfall events took place almost back-to-back during July and August, while in Karachi, the downpours were the most intense on record since 1931.

Scientists note that as the planet warms, the total monsoon rain will increase, though some areas will receive less rainfall due to changes in wind patterns.

This means that heavy rainfall events such as those seen in Pakistan this year will likely become more frequent.

Estimated cost: $1.5 billion

Men ride on a motorbike along a flooded street after heavy monsoon rains in Pakistan's port city of Karachi on August 31. Picture: Asif Hassan/AFP
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(USA) Joe Biden Takes Climate Change Seriously

New York Times - Editorial

Illustration by Michael Houtz; photographs by Getty Images
As President-elect Joe Biden rolls out his climate and environment team, it is worth recalling, if only to grasp the distance between then and now, the hopeless bunch President-elect Donald Trump presented us with four years ago. Mr. Trump tapped Scott Pruitt to run the Environmental Protection Agency, Ryan Zinke the Interior Department and Rick Perry the Energy Department.

Mr. Pruitt, by common consent the worst of the mediocrities in Mr. Trump’s cabinet, helped persuade him to withdraw from the Paris Agreement on climate change and set in motion the rollback of every important regulation approved by the Obama administration to reduce greenhouse gases. Mr. Zinke, in plain imitation of Teddy Roosevelt, rode a horse to work on his first day on the job, but within a year had ceded to the oil, gas and coal industries millions of acres of public land that Mr. Roosevelt would almost certainly have tried to protect. In Mr. Perry, Mr. Trump chose a man who back in 2011 recommended the abolition of the very department Mr. Trump was asking him to run.

The Biden team is as different as different can be. For starters, it actually cares about climate. In the two people the president-elect has chosen to be his top advisers in the White House, there is even an element of poetic justice.

One is John Kerry, the former secretary of state who helped orchestrate the Paris Agreement that Mr. Trump so quickly abandoned, and whose main job now will be to restore America’s global credibility and leadership position on the climate issue. The second is Gina McCarthy, who will help devise and direct Mr. Biden’s domestic policy response, making sure that all agencies of government are pulling in the same direction. As with Mr. Kerry, her solid achievements while serving as Barack Obama’s E.P.A. administrator were undone by Mr. Trump, including rules aimed at sharply reducing greenhouse gases from vehicles, power plants and oil and gas operations. It will require great charity on her part not to take some satisfaction in seeing these rules restored.

The people Mr. Biden has named to key posts in the various federal agencies are no less committed, including an economic team led by Brian Deese, who quarterbacked Mr. Obama’s climate program. Jennifer Granholm, a two-term Michigan governor and a champion of renewable energy, was selected to run the Energy Department, which is entrusted with finding breakthrough technologies. Pete Buttigieg, a former mayor of South Bend, Ind., who was among Mr. Biden’s challengers for the Democratic nomination, has been designated to lead a Transportation Department with an important role in developing climate-friendly mass transit. Deb Haaland, a member of Congress and Democrat from New Mexico, was named to be the interior secretary.

The Haaland appointment is interesting, and not just for symbolic reasons. True, she would be the first Native American appointed to a cabinet secretary position. Critically important, from a climate perspective, she would oversee 500 million acres of federal land, including national parks and wilderness and mixed-use land, which under her predecessors — first Mr. Zinke, then David Bernhardt, an oil industry lobbyist — were increasingly given over to drilling, mining, logging and development, all the things that enable greenhouse gases and that a good climate policy does not want.

There are, of course, other reasons for leaving some lands completely alone — to protect endangered species and clean water sources, for instance, and simply for the enjoyment of future generations. To those we can now add the imperative of slowing climate change.

The only controversy in this selection process involved the E.P.A. Mr. Biden’s first choice was reportedly Mary Nichols, who worked at the agency years ago before becoming California’s air quality regulator and arguably the nation’s most energetic voice on climate change. But activists claimed that she had ignored air quality concerns in disadvantaged neighborhoods, and while their policy arguments were largely specious, this was a fight Mr. Biden did not need. Besides, he had already recruited Ms. McCarthy, who is generationally and ideologically on the same wavelength as Ms. Nichols.

So he chose instead Michael Regan, North Carolina’s top environmental regulator, who did much good in a state where progress on environmental issues has never been easy. Mr. Regan would be the second Black person to run the E.P.A., the first being Lisa Jackson, who served in Mr. Obama’s first term. It will fall to the new administrator to revive agency morale, give science its rightful place in decision-making and restore, in addition to the Obama emissions rules, the broad powers of the Clean Water Act, which were narrowed under Mr. Trump.

All in all, a handsome batch of résumés, but résumés won’t match the urgent challenge ahead. How urgent? Just over two years ago, the Intergovernmental Panel on Climate Change, the world’s pre-eminent authority on global warming, warned that the world must transform its energy systems by midcentury in order to limit warming to 1.5 degrees Celsius above preindustrial levels, or risk widespread ecological and social disruptions — including but not limited to die-offs of coral reefs, sea level rise, drought, famine, wildfires and potential migrations of whole populations searching for food and fresh water. More pointedly, it stressed that the next decade was crucial, that emissions would have to be on a sharp downward path by 2030 for any hope of success, that there was no gentle glide path and that the world’s political leaders would have to take a firm grip on the emissions curve and wrench it downward in a hurry.

With that in mind, Mr. Biden pledged to achieve net zero emissions by 2050 and, along the way, eliminate fossil fuel emissions from the power sector by 2035. What this in turn is likely to require is set forth in a detailed Princeton study, summarized by The Times’s Brad Plumer on Dec. 15: a doubling, annually, in the pace of new wind and solar power; a huge increase in the number of new battery-powered cars sold every year, from 2 percent now to 50 percent of new sales by 2030, with charging stations to serve them; a big jump in the number of homes heated by electric heat pumps instead of oil and gas; and, necessarily, a vast increase in the capacity of the electric grid to handle all this clean power.

This transformation of the energy delivery system will not be achieved by regulation, although that will surely help, or, as some groups seem to believe, by simply ending hydraulic fracturing for oil and gas. What the Princeton study envisions is great amounts of new public and private investment, bigger by far than the modest energy-related tax breaks in the year-end spending and coronavirus relief package (which also, happily, included a provision that would curtail the use of planet-warming refrigerants called HFCs, thus bringing the United States in alignment with the rest of the world).

Extracting the necessary trillions from a potentially divided Congress is the tallest of tall orders. The betting now is on two possible legislative paths, maybe both: a stimulus bill with all sorts of green investments tucked into it, along the lines of the 2009 Obama stimulus but much bigger; and, after that, a big infrastructure bill targeted at projects that will reduce greenhouse gas emissions.

Mr. Biden’s strategy is still in the making. But whatever path he chooses, progress in this still-fractured country will require all the energy and smart ideas his team can muster and all the negotiating skills Mr. Biden himself has acquired in a half-century of public service.

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30/12/2020

Land Ecosystems Are Becoming Less Efficient At Absorbing CO2

NASA -  Esprit Smith

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 CO2 fertilization 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."

A Pacific Ocean phenomena with impacts around the world. Read more
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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