More livestock, more carbon dioxide, less ice: the world’s climate change progress since 2019 is (mostly) bad news


Thomas Newsome, University of Sydney; Christopher Wolf, Oregon State University, and William Ripple, Oregon State UniversityBack in 2019, more than 11,000 scientists declared a global climate emergency. They established a comprehensive set of vital signs that impact or reflect the planet’s health, such as forest loss, fossil fuel subsidies, glacier thickness, ocean acidity and surface temperature.

In a new paper published today, we show how these vital signs have changed since the original publication, including through the COVID-19 pandemic. In general, while we’ve seen lots of positive talk and commitments from some governments, our vital signs are mostly not trending in the right direction.

So, let’s look at how things have progressed since 2019, from the growing number of livestock to the meagre influence of the pandemic.

Is it all bad news?

No, thankfully. Fossil fuel divestment and fossil fuel subsidies have improved in record-setting ways, potentially signalling an economic shift to a renewable energy future.

The graph on the left shows an increase in fossil fuel divestment by 1,117 organisations based on data from 350.org, and the graph on the right shows a decrease in subsidies for fossil fuels based on the International Energy Agency subsidies database. The red lines show changes since our original publication in 2019.

However, most of the other vital signs reflect the consequences of the so far unrelenting “business as usual” approach to climate change policy worldwide.

Especially troubling is the unprecedented surge in climate-related disasters since 2019. This includes devastating flash floods in the South Kalimantan province of Indonesia, record heatwaves in the southwestern United States, extraordinary storms in India and, of course, the 2019-2020 megafires in Australia.

In addition, three main greenhouse gases — carbon dioxide, methane and nitrous oxide — set records for atmospheric concentrations in 2020 and again in 2021. In April this year, carbon dioxide concentration reached 416 parts per million, the highest monthly global average concentration ever recorded.

Time series of three climate-related responses. The red lines show changes since our original publication in 2019.

Last year was also the second hottest year in recorded history, with the five hottest years on record all occurring since 2015.

Ruminant livestock — cattle, buffalo, sheep, and goats — now number more than 4 billion, and their total mass is more than that of all humans and wild mammals combined. This is a problem because these animals are responsible for impacting biodiversity, releasing huge amounts of methane emissions, and land continues to be cleared to make room for them.

There are now more than 4 billion livestock on Earth.
Flickr

In better news, recent per capita meat production declined by about 5.7% (2.9 kilograms per person) between 2018 and 2020. But this is likely because of an outbreak of African swine fever in China that reduced the pork supply, and possibly also as one of the impacts of the pandemic.

Tragically, Brazilian Amazon annual forest loss rates increased in both 2019 and 2020. It reached a 12-year high of 1.11 million hectares deforested in 2020.

Ocean acidification is also near an all-time record. Together with heat stress from warming waters, acidification threatens the coral reefs that more than half a billion people depend on for food, tourism dollars and storm surge protection.

Map of land-ocean temperature index anomaly in June, relative to the 1951-1980 baseline.
Oregon State/NASA

What about the pandemic?

With its myriad economic interruptions, the COVID-19 pandemic had the side effect of providing some climate relief, but only of the ephemeral variety.

For example, fossil-fuel consumption has gone down since 2019 as did airline travel levels.

But all of these are expected to significantly rise as the economy reopens. While global gross domestic product dropped by 3.6% in 2020, it is projected to rebound to an all-time high.

So, a major lesson of the pandemic is that even when fossil-fuel consumption and transportation sharply decrease, it’s still insufficient to tackle climate change.

There is growing evidence we’re getting close to or have already gone beyond tipping points associated with important parts of the Earth system, including warm-water coral reefs, the Amazon rainforest and the West Antarctic and Greenland ice sheets.

Warming waters are threatening West Antarctic and Greenland ice sheets.
Flickr

OK, so what do we do about it?

In our 2019 paper, we urged six critical and interrelated steps governments — and the rest of humanity — can take to lessen the worst effects of climate change:

  1. prioritise energy efficiency, and replace fossil fuels with low-carbon renewable energy
  2. reduce emissions of short-lived pollutants such as methane and soot
  3. curb land clearing to protect and restore the Earth’s ecosystems
  4. reduce our meat consumption
  5. move away from unsustainable ideas of ever-increasing economic and resource consumption
  6. stabilise and, ideally, gradually reduce human populations while improving human well-being especially by educating girls and women globally.

These solutions still apply. But in our updated 2021 paper, we go further, highlighting the potential for a three-pronged approach for near-term policy:

  1. a globally implemented carbon price
  2. a phase-out and eventual ban of fossil fuels
  3. strategic environmental reserves to safeguard and restore natural carbon sinks and biodiversity.

A global price for carbon needs to be high enough to induce decarbonisation across industry.

And our suggestion to create strategic environmental reserves, such as forests and wetlands, reflects the need to stop treating the climate emergency as a stand-alone issue.

By stopping the unsustainable exploitation of natural habitats through, for example, creeping urbanisation, and land degradation for mining, agriculture and forestry, we can reduce animal-borne disease risks, protect carbon stocks and conserve biodiversity — all at the same time.

A kangaroo in burnt bushland
There has been a worrying number of disasters since 2019, including Australia’s megafires.
Shutterstock

Is this actually possible?

Yes, and many opportunities still exist to shift pandemic-related financial support measures into climate friendly activities. Currently, only 17% of such funds had been allocated that way worldwide, as of early March 2021. This percentage could be lifted with serious coordinated, global commitment.

Greening the economy could also address the longer term need for major transformative change to reduce emissions and, more broadly, the over-exploitation of the planet.

Our planetary vital signs make it clear we need urgent action to address climate change. With new commitments getting made by governments all over the world, we hope to see the curves in our graphs changing in the right directions soon.




Read more:
11,000 scientists warn: climate change isn’t just about temperature


The Conversation


Thomas Newsome, Academic Fellow, University of Sydney; Christopher Wolf, Postdoctoral Scholar, Oregon State University, and William Ripple, Distinguished Professor and Director, Trophic Cascades Program, Oregon State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Artificial refuges are a popular stopgap for habitat destruction, but the science isn’t up to scratch


Shutterstock

Darcy Watchorn, Deakin University; Dale Nimmo, Charles Sturt University; Mitchell Cowan, Charles Sturt University, and Tim Doherty, University of SydneyWildlife worldwide is facing a housing crisis. When land is cleared for agriculture, mining, and urbanisation, habitats and natural refuges go with it, such as tree hollows, rock piles and large logs.

The ideal solution is to tackle the threats that cause habitat loss. But some refuges take hundreds of years to recover once destroyed, and some may never recover without help. Tree hollows, for example, can take 180 years to develop.

As a result, conservationists have increasingly looked to human-made solutions as a stopgap. That’s where artificial refuges come in.

If the goal of artificial refuges is to replace lost or degraded habitat, then it is important we have a good understanding of how well they perform. Our new research reviewed artificial refuges worldwide — and we found the science underpinning them is often not up to scratch.

What are artificial refuges?

Artificial refuges provide wildlife places to shelter, breed, hibernate, or nest, helping them survive in disturbed environments, whether degraded forests, deserts or urban and agricultural landscapes.

Nest boxes are a commonly used artificial refuge for tree-dwelling animals.
Ed Reinsel/Shutterstock

You’re probably already familiar with some. Nest boxes for birds and mammals are one example found in many urban and rural areas. They provide a substitute for tree hollows when land is cleared.

Other examples include artificial stone cavities used in Norway to provide places for newts to hibernate in urban and agricultural environments, and artificial bark used in the USA to allow bats to roost in the absence of trees. And in France, artificial burrows provide refuge for lizards in lieu of their favoured rabbit burrows.

An artificial burrow created for a burrowing owl.
AZ Outdoor Photography/Shutterstock

But do we know if they work?

Artificial refuges can be highly effective. In central Europe, for example, nest boxes allowed isolated populations of a colourful bird, the hoopoe, to reconnect — boosting the local genetic diversity.

Still, they are far from a sure thing, having at times fallen short of their promise to provide suitable homes for wildlife.




Read more:
DIY habitat: my photos show chainsaw-carved tree hollows make perfect new homes for this mysterious marsupial


One study from Catalonia found 42 soprano pipistrelles (a type of bat) had died from dehydration within wooden bat boxes, due to a lack of ventilation and high sun exposure.

Another study from Australia found artificial burrows for the endangered pygmy blue tongue lizard had a design flaw that forced lizards to enter backwards. This increased their risk of predation from snakes and birds.

And the video below from Czech conservation project Birds Online shows a pine marten (a forest-dwelling mammal) and tree sparrow infiltrating next boxes to steal the eggs of Tengmalm’s owls and common starlings.

The effects of predation should be considered when using artificial refuges.

So why is this happening?

Our research investigated the state of the science regarding artificial refuges worldwide.

We looked at more than 220 studies, and we found they often lacked the rigour to justify their widespread use as a conservation tool. Important factors were often overlooked, such as how temperatures inside artifical refuges compare to natural refuges, and the local abundance of food or predators.

Alarmingly, just under 40% of studies compared artificial refuges to a control, making it impossible to determine the impacts artificial refuges have on the target species, positive or negative.

This is a big problem, because artificial refuges are increasingly incorporated into programs that seek to “offset” habitat destruction. Offsetting involves protecting or creating habitat to compensate for ecological harm caused by land clearing from, for instance, mining or urbanisation.

For example, one project in Australia relied heavily on nest boxes to offset the loss of old, hollow-bearing trees.

But a scientific review of the project showed it to be a failure, due to low rates of uptake by target species (such as the superb parrot) and the rapid deterioration of the nest boxes from falling trees.




Read more:
The plan to protect wildlife displaced by the Hume Highway has failed


The future of artificial refuges

There is little doubt artificial refuges will continue to play a role in confronting Earth’s biodiversity crisis, but their limitations need to be recognised, and the science underpinning them must improve. Our new review points out areas of improvement that spans design, implementation, and monitoring, so take a look if you’re involved in these sorts of projects.

We also urge for more partnerships between ecologists, engineers, designers and the broader community. This is because interdisciplinary collaboration brings together different ways of thinking and helps to shed new light on complex problems.

Some key steps arising from our research which suggest a way forward for artificial refuge science and implementation.
Author provided

It’s clear improving the science around artificial refuges is well worth the investment, as they can give struggling wildlife worldwide a fighting chance against further habitat destruction and climate change.




Read more:
To save these threatened seahorses, we built them 5-star underwater hotels


The Conversation


Darcy Watchorn, PhD Candidate, Deakin University; Dale Nimmo, Associate Professor in Ecology, Charles Sturt University; Mitchell Cowan, PhD Candidate, Charles Sturt University, and Tim Doherty, ARC DECRA Fellow, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.