China Contributes 10% of Human Influence on Climate Change
China accounts for a tenth of all the greenhouse gases and aerosols that have collected in the atmosphere over the industrial era, according to new research.
Boasting one of the world’s largest economies, China has overtaken the EU and the U.S. as the world’s largest emitter, with CO2 emissions from fossil fuels tripling over the past 30 years.
It’s a pretty complicated picture. But in recent times, this is because cooling from aerosols has been masking part of the warming signal. The upshot of this is that cutting some types of aerosol in a much-needed bid to improve air quality could drive faster warming in the coming decades, say the authors.
The new study quantifies all the gases and particles currently in the atmosphere that are having an effect on global temperature and which can be traced back to human activity.
The authors combined this with China’s past and present emissions to estimate, for the first time, the size of the country’s total contribution to human-caused climate change.
Unlike aerosols, greenhouse gases stay in the atmosphere for a very long time. Carbon dioxide emitted at the start of the industrial revolution is still warming the atmosphere today, which is why scientists take into account historical emissions as well as present day ones to work out a country’s contribution to climate change.
The graph below (main, not inset) shows the impact on global temperature—known as the radiative forcing—from different anthropogenic sources of greenhouse gases in China extending back to 1850.
China’s single biggest source of warming is CO2 from fossil fuel burning (red line). With emissions rising steeply over the past few decades, fossil fuels overtook land-use change as the biggest source of CO2 from China in 1992 (brown line).
Warming as a result of changing land use rose throughout the 20th century, before declining in the 1980s as reforestation programs turned the land from a net emitter to a net absorber.
“China is now planting forests on a larger scale than anywhere else on the planet. These plantations sequester CO2 from the atmosphere, so that Chinese forests are now a net sink of this gas.”
Despite this, past emissions from land-use change still account for a third of atmospheric CO2 attributable to China, with fossil-fuel burning making up the other two thirds, the paper notes.
The warming caused by emissions of nitrous oxide (yellow) and halogen compounds (pink) increased over the past two or three decades—to a far lesser extent than fossil fuel CO2, while methane-induced warming increased three-fold between 1950-2010 (orange line).
To put the changes within China into a global context, the inset graph in the figure above shows the warming effect of Chinese greenhouse gases as a percentage of the global total.
Again, the impact of China’s recent fossil fuel expansion is clear, with the country’s contribution to total global fossil fuel CO2 almost tripling in the 30-year period between 1980-2010.
China currently accounts for 12 percent of the total greenhouse gases in the atmosphere—a figure that has remained fairly steady over the industrial period, at around 8-12 percent (blue line). This is effectively the balance of impacts from all China’s greenhouse gas emissions over time—i.e. carbon dioxide, methane, nitrous oxide and halogen compounds—and from all anthropogenic sources.
The 10 percent figure is lower than might be expected for the country topping of the list of the biggest emitters. But it reflects the fact that others, such as the U.S. and the EU, have been emitting far longer, the paper notes. The paper does not calculate the contributions from these other entities, so a direct comparison is not possible.
Relative to the rest of the world, China’s share of greenhouse gas warming fell slightly in the 1960s, 70s and 80s before starting to climb again as economic growth and fossil fuel burning accelerated.
But there’s something else going on, too. China is responsible for a disproportionate amount of the aerosols emitted around the world, some of which have a strong cooling effect.
According to the new study’s results, China is responsible for 28 percent of the sulphate aerosols currently in the atmosphere (light blue bar in the graph below), 24 percent of nitrate aerosols (dark blue) and 14 percent of black carbon (pink).
Importantly, while the U.S. and Europe have been slashing sulphates in an effort to improve air quality, China’s aerosol emissions have been on the rise. Spracklen said:
“Air pollution is a serious environmental issue in China, where 1.3m people die each year because of exposure to poor-quality air outdoors.”
As well as posing a growing public health crisis, sulphate aerosols have a strong cooling effect. Over the past few decades, this has been pulling in the opposite direction to rising CO2, methane and black carbon emissions, effectively muting China’s relative impact on global temperature.
As the graph below from Spracklen’s News and Views article shows, the balance between warming (red shading) and cooling (blue shading) have kept the country’s contribution to human-caused climate change pegged at about 10 percent in recent decades, despite soaring fossil fuel emissions.
The implication is that if China follows the rest of the world in cutting sulphate aerosols in a bid to reduce air pollution, global temperatures could rise even faster in the coming decades since there would be less of a cooling effect to offset the warming. But this is no reason to avoid doing it, said Spracklen:
“This means that it will be difficult to achieve rapid reductions in near-term global warming through the control of Chinese air pollutants overall—a focus on greenhouse-gas emissions, in particular, will be required.”
But given the upwards trend in fossil fuel CO2 emissions, the long lifetimes of existing infrastructure and the social and political systems in place, it is “unlikely” that China’s relative contribution to global greenhouse gas warming will come down any time soon, say the authors in the paper.
While the study goes further than previous ones in terms of pinning down China’s total contribution to climate change, the authors acknowledge a lot of remaining uncertainty, particularly about China’s methane and sulphur dioxide emissions.
There is also work to be done in completing the complex picture of influencing factors. For example, the authors acknowledge the role of aerosols in stimulating clouds to form and the darkening of snow and ice by black carbon, adding that there is still too much uncertainty to include fully in their calculations.
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America's largest national forest, Tongass National Forest in Alaska, will be opened up to logging and road construction after the Trump administration finalizes its plans to open up the forest on Friday, according to The New York Times.
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By Ruby Russell and Ajit Niranjan
Hamstrung by coronavirus lockdowns, frustrated school strikers have spent months staging digital protests against world leaders failing to act urgently on climate change.
Pandemic Stalls Protests<p>Last November, the head of the UN Environment Program was among the public and scientific figures to warn that 2020 offered a last chance to cut emissions. Then, few could have suspected this deadline would coincide with an unprecedented public health emergency.</p><p>The pandemic has <a href="https://www.dw.com/en/tough-times-ahead-for-climate-protesters-during-corona-pandemic/a-52978469" target="_blank">dealt climate activism a blow</a>. Niedeggen says that as a movement demanding that the world act on scientific advice, the school strikers took lockdown restrictions extremely seriously, halted public protests immediately and took their activism online.</p><p>On April 24, Fridays for Future organized a "digital strike," with Niedeggen hosting a that racked up close to a quarter of a million views. "We were not physically standing together, but we were all fighting together," she says.</p><p><a href="https://www.dw.com/en/climate-strikers-get-inventive-during-the-covid-19-crisis-fridays-for-future/a-53229262" target="_blank" rel="noopener noreferrer">Activists also gathered thousands of placards</a> from across Germany to lay out in front of the German Bundestag around the central slogan: "Fight every crisis."</p>
Opportunity for a New Normal<p>Last September's Global Climate Strike drew young and old protestors around the world, with organizers estimating a global turnout of 7.6 million, including an estimated 270,000 people in Berlin. Activists have adjusted this year's event to account for social distancing and different levels of coronavirus restrictions in cities taking part.</p><p>They say COVID-19 also presents opportunities.</p><p>"The pandemic shows that we can change our normal daily life, and we are very able to adjust to a situation of crisis," she says. The key question is how economies get back on their feet: "We have the possibility to build a new normal, to build a renewable world order, and an environmentally just, climate-just normal for everybody."</p><p>In July, Jeng was among 20 female Fridays for Future activists from the Global South to sign an open letter to G20 finance ministers warning that their decisions in "exclusive backrooms" over stimulus packages and corporate bailouts would "lock in development pathways for decades."</p><p>"The system is not broken, it was built to be unjust. We don't need recovery, we need a reboot," the letter reads, stressing that "black people, indigenous peoples and people of color," have been disproportionately hit by the economic, climate and coronavirus crises. </p>
Policy 'Not Quite There Yet'<p>Figures on stimulus spending do not suggest their words had much impact. The ministers were criticized for failing to relieve the debt of poorer countries, and according to <a href="https://www.energypolicytracker.org/region/g20/" target="_blank" rel="noopener noreferrer">Energy Policy Tracker</a>, G20 countries by August had pledged $169 billion (142 billion euros) to fossil fuels since the beginning of the pandemic.</p><p>Katrin Uba, associate professor of political science at Uppsala University in Sweden, is researching Fridays for Future. She says that despite the movement raising awareness and gaining access to policymakers, real policy change "is not there yet."</p><p>Still, she stresses that social movements go through waves of mobilization as public attention on their core issues ebbs and flows. And perhaps one of Fridays for Future's biggest achievements is birthing a politically active generation that will keep the fight up long after corona becomes a memory. </p><p>"We know clearly from our research that many of the people who came to the streets hadn't done any protesting before in their lives," she told DW. "And we also know that if you do one protest, you are likely to do more."</p>
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This week marks the official start of fall, but longer nights and colder days can make it harder to spend time outdoors. Luckily, there are several inspiring environmental films that can be streamed at home.
1. Kiss the Ground<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="ccc5f0c92a5603e68aec39e56b0db02a"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/K3-V1j-zMZw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p><strong>Streaming On: Netflix</strong></p><p><strong>Premiere Date: Sept. 22</strong></p><p>Between <a href="https://www.ecowatch.com/wildfires-california-washington-oregon-photos-2647585008.html" target="_self">wildfires devastating the U.S. West Coast</a> and <a href="https://www.ecowatch.com/tropical-storm-beta-landfall-2647760268.html" target="_self">storms battering the Gulf</a>, the impacts of the <a href="https://www.ecowatch.com/climate-change/" target="_self">climate crisis</a> can feel overwhelming right now. <em><a href="https://kissthegroundmovie.com/" rel="noopener noreferrer" target="_blank">Kiss the Ground</a> </em>offers an alternative to all of the bad news by focusing on solutions.</p><p>The film, directed by Josh and Rebecca Tickell and narrated by Woody Harrelson, explains how we can heal the Earth through "regenerative agriculture," farming practices that draw carbon dioxide from the atmosphere and into soil as a way to restore soil health, which in turn boosts ecosystems and food supplies.</p><p>"<em>Kiss the Ground </em>shows how feasible it is to make these changes at a grassroots level immediately and make a truly substantive impact with low cost and easy to implement solutions," Executive Producer RJ Jain said in an email. "This is why I got involved."</p>
2. Public Trust: The Fight for America's Public Lands<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="5338f7a2931e356910026e5fd76fac56"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/jsKMTAaj_wQ?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p><strong>Streaming On: YouTube</strong></p><p><strong>Premiere Date: Sept. 25</strong></p><p>This <a href="https://www.patagonia.com/films/public-trust/" target="_blank">award-winning documentary</a> tells the stories of Indigenous activists, journalists, whistleblowers and historians working to protect America's <a href="https://www.ecowatch.com/tag/public-lands" target="_self">public lands</a>. The film focuses on three political struggles: the shrinking of <a href="https://www.ecowatch.com/tag/bears-ears" target="_self">Bears Ears</a> National Monument in Utah, the mining of Boundary Waters Wilderness in Minnesota and the opening of the <a href="https://www.ecowatch.com/tag/Arctic-National-Wildlife-Refuge" target="_self">Arctic National Wildlife Refuge</a> to fossil fuel exploration.</p><p><em>Public Trust</em> was directed by David Garrett Byars and produced by Jeremy Rubingh. Patagonia Films, Patagonia founder Yvon Chouinard and actor Robert Redford are executive producers. It will be <a href="https://www.youtube.com/watch?v=OGjnIG7puzY" rel="noopener noreferrer" target="_blank">released</a> on YouTube in time for <a href="https://www.ecowatch.com/national-public-lands-day-2640656776.html" target="_self">National Public Lands Day</a>.</p><p>"Our country is fortunate to have millions of acres of public lands, including National Parks, Monuments, Wildlife Refuges and Wilderness set aside for future generations," Redford said. "Sadly, these lands that belong to you and me are under unprecedented threats from the greed of big corporations, eager to weaken restrictions in the pursuit of profits. Many of our current politicians are also to blame. <em>Public Trust</em> tells the story of citizens who are fighting back. It's a much-needed wake-up call for all of us who want to preserve our unique and wild cultural heritage."<br><br>It will be <a href="https://www.youtube.com/watch?v=OGjnIG7puzY" target="_blank">released</a> on YouTube at 2 p.m. EDT Friday in time for <a href="https://www.ecowatch.com/national-public-lands-day-2640656776.html" target="_self">National Public Lands Day</a>.<br></p>
3. David Attenborough: A Life on Our Planet<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="156438a30836a765d7a92982545fc334"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/B_OFZvAd05Y?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p><strong>Streaming On: Netflix</strong></p><p><strong>Premiere Date: Oct. 4</strong></p><p>Beloved nature broadcaster <a href="https://www.ecowatch.com/tag/David-Attenborough" target="_self">David Attenborough</a> has spent his career introducing viewers to the wonders of our planet. In recent years, his footage of albatrosses swallowing <a href="https://www.ecowatch.com/tag/plastics" target="_self">plastic</a> in <em>Blue Planet II</em> has been credited with <a href="https://www.ecowatch.com/2018-fighting-plastic-waste-2624606566.html" target="_self">helping to ramp up</a> the global fight against plastic pollution. Now, in this <a href="https://www.wwf.org.uk/" rel="noopener noreferrer" target="_blank">World Wildlife Fund</a> (WWF)-produced <a href="https://www.attenborough.film/" rel="noopener noreferrer" target="_blank">documentary</a>, he reflects on the defining moments of his career and the devastating changes he has witnessed.</p><p><em>David Attenborough: A Life on Our Planet,</em> which was also produced by Silverback Films and directed by Alastair Fothergill, Jonnie Hughes and Keith Scholey, features an intimate conversation between Attenborough and Sir Michael Palin as the broadcaster reflects on his life and a career that took him to every continent on Earth. In addition to streaming on Netflix, the movie will be available in select theaters starting Sept. 28.</p><p>"For decades, David has brought the natural world to the homes of audiences worldwide, but there has never been a more significant moment for him to share his own story and reflections," WWF executive producer Colin Butfield said in a <a href="https://www.wwf.org.uk/updates/david-attenborough-life-our-planet" target="_blank">statement</a>. "This film coincides with a monumental year for environmental action as world leaders make critical decisions on nature and climate. It sends a powerful message from the most inspiring and celebrated naturalist of our time."</p>
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