With the possible prospect of the world warming dangerously and uncontrollably, half of one degree Celsius may sound like a negligible temperature change unlikely to make much difference to life on Earth.

But scientists say 0.5 C could make a crucial difference in some regions—particularly in developing countries in the tropics—that are already at great risk from climate change. The consequences could include higher sea level rise and extended heatwaves, threatening most tropical coral reefs.

Bill Hare, CEO of Climate Analytics and a member of the research team that has produced the cautionary report, said: “Our study shows that tropical regions—mostly developing countries that are already highly vulnerable to climate change—face the biggest rise in impacts between 1.5 C and 2 C.

Vulnerable Countries

“Our results add to a growing body of evidence showing that climate risks occur at lower levels than previously thought. They provide scientific evidence to support the call by vulnerable countries, such as the Least Developed Countries and Small Island Developing States, that a 1.5 C warming limit would substantially reduce the impacts of climate change.”

The Paris agreement on climate change being signed today in New York was concluded at last December’s UN climate conference. It aims to keep global average temperatures “well below” the 2 C previously agreed—and to pursue efforts to limit the increase to 1.5 C.

But the report by European researchers—published in Earth System Dynamics, an open access journal of the European Geosciences Union (EGU)—says they have found that there would be substantially different impacts for the two targets by 2100. They say the extra 0.5 C would mean a global sea-level rise of 10 centimeters, longer heatwaves and would put virtually all tropical coral reefs at risk.

“We found significant differences for all the impacts we considered,” said the study’s lead author, Carl-Friedrich Schleussner, a physicist at Climate Analytics.

“We analyzed the climate models used in the Intergovernmental Panel on Climate Change’s Fifth Assessment Report, focusing on the projected impacts at 1.5 C and 2 C warming at the regional level. We considered 11 different indicators, including extreme weather events, water availability, crop yields, coral reef degradation and sea-level rise.”

The team, including researchers from Germany, Switzerland, Austria and the Netherlands, identified a number of hotspots around the globe where projected climate impacts at 2 C are significantly more severe than at 1.5 C.

One of these is the Mediterranean region, already experiencing climate change-induced drying. With a global temperature increase of 1.5 C, the availability of fresh water in the region would be about 10 percent lower than in the late 20th century. But in a 2 C world, the researchers project that this reduction would double to about 20 percent.

In tropical regions, the half-a-degree difference in global temperature could damage crop yields, particularly in Central America and West Africa. On average, local tropical maize and wheat yields would fall twice as much with a 2 C temperature increase as with 1.5 C.

By 2100, tropical regions would also experience warm spells lasting up to 50 percent longer in a 2 C world than at 1.5 C. “For heat-related extremes, the additional 0.5 C increase marks the difference between events at the upper limit of present-day natural variability and a new climate regime, particularly in tropical regions,” Schleussner said.

The extra warming would also affect tropical coral reefs. Limiting warming to 1.5 C would provide a window of opportunity for some reefs to adapt to climate change, but a 2 C increase by 2100 would put virtually all of them at risk of severe degradation from coral bleaching.

Large-scale Bleaching

Australian researchers say 93 percent of the Great Barrier Reef, off the coast of Queensland, is affected to some degree by bleaching. They say large-scale bleaching has also been found off Australia’s west coast.

In the EGU study, the researchers say they expect sea level to rise by about 50 cm by 2100 in a 2 C warmer world, 10 cm more than for 1.5 C warming. These levels are appreciably lower than some scientists expect.

“Sea level rise will slow down during the 21st century only under a 1.5 C scenario,” Dr. Schleussner warns.

One of his co-authors, Jacob Schewe, a climate physicist at the Potsdam Institute for Climate Impact Research, Germany, says it is necessary to account for natural variability, model uncertainties and other factors that could obscure the picture.

“We did that in our study,” he said. “And by focusing on key indicators at the regional level, we clearly show that there are significant differences in impacts between 1.5 C and 2 C.”

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By The Climate Mobilization

When establishment civil society groups and politicians gather Friday to cheer the signing of the Paris agreement as a “historic" achievement that will avert global catastrophe, a group of climate emergency protesters will stage a “mass death" and collapse scenario outside the United Nations to demonstrate the reality of the future the agreement locks in.

The protesters will act out the collapse of global civilization that will occur if humanity remains on the Paris agreement's non-binding emissions trajectory toward a world 3.5 C hotter than the pre-industrial period.

More specifically, they will enact the mass starvations the agreement ensures, erect grave stones for the nation-states that will collapse under the stress of extreme drought and water scarcity and play the government and civil society bureaucrats who pretend that the situation is under control and that business-as-usual reforms can protect humanity and the natural world.

Speakers will include Theravadan Buddhist monk Bhikkhu Bodhi and the Climate Mobilization's Founders Margaret Klein Salamon and Ezra Silk. All of the speakers will call for an emergency, World War II-scale mobilization that eliminates global net greenhouse gas emissions by 2030 and restores a safe and stable climate by drawing down all excess carbon dioxide and cooling the planet from the dangerously high temperatures reached in recent months and years.

The Paris agreement calls for net zero greenhouse gas emissions at some point “in the second half of this century" and does not directly cover aviation, shipping or agriculture, which collectively account for, at minimum, between a quarter and a third of global greenhouse gas emissions. In the first three months of 2016, global average temperature anomalies approached and surpassed the limits called for in the agreement, rendering its gradual emissions trajectory irrelevant and dangerous.

“The Paris agreement is historic in the sense that the Munich Agreement was historic—a catastrophic act of appeasement meant to maintain business-as-usual arrangements," said Climate Mobilization Deputy Director Ezra Silk. “Leading economists argue that climate change could cause at least as much destruction as World War II—and the non-binding Paris agreement paves the way for that future. It's time to stop waiting for another climate 'Pearl Harbor' and to mobilize all available resources to save human civilization."

The Climate Mobilization is sponsoring the event with the support of the People's Climate Movement New York. Since last fall, the Climate Mobilization has pressured all Democratic and Republican presidential contenders to endorse a WWII-scale mobilization to restore a safe climate. Last week, Bernie Sanders embraced the idea at the CNN debate held at the Brooklyn Navy Yard, which played a pivotal role in the World War II home front mobilization of the 1940s.

“Of course the [Paris] agreement is a step forward, but you know agreements and I know agreements, there's a lot of paper there," Sanders said. “If we approach this, Errol, as if we were literally at a war—you know, in 1941, under Franklin Delano Roosevelt, we moved within three years, within three years to rebuild our economy to defeat Nazism and Japanese imperialism. That is exactly the kind of approach we need right now."

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On Earth Day 150 World Leaders to Sign Paris Climate Agreement

Which Countries Won't Be Signing the Paris Climate Deal on Earth Day?

An unprecedented number of countries will be gathering in New York City tomorrow to sign the Paris climate deal.

After significant progress was made this past December in agreeing the landmark deal, more than 167 countries—including past climate villains Iran, Canada and Australia and polluting giants China, the U.S. and the EU—are set to sign the Paris agreement on its opening day.

But despite this, there are still some countries that remain absent from the UN’s official list of attendees—and this includes some pretty big emitters and fossil fuel producers.

So while much focus has been on who will be signing the Paris agreement on April 22, here we take a look at those that might not be.

Russia and the Commonwealth of Independent States (CIS)

There have been a lot of questions about whether or not Russia would attend.

Up until April 20, it was the largest emitter and producer absent from the UN’s list is Russia, dwarfing other non-signatories, representing more than five percent of annual global emissions.

But according to a new list updated by the UN, Russia has now indicated that it will be attending the New York ceremony tomorrow.

The country’s president Vladimir Putin has previously described climate change as a conspiracy to diminish the country’s power, but changed his tone (though not necessarily increasing Russia’s ambition) at the opening ceremony of COP21 in Paris.

Russian newspaper Kommersant hinted at progress there reporting that some ministries have begun submitting draft implementation measures for the Paris agreement.

As Vladimir Chuprov, Head of the Energy Unit at Greenpeace Russia told DeSmog UK, a Russian Federation governmental order stated that the country would sign the agreement.

World Wildlife Fund’s Alexey Kokorin echoed Chuprov’s comments, saying Deputy Prime Minister Alexander Khloponin will sign on behalf of Russia in spite of hard lobbying of coal and steel companies.

There are however still some Commonwealth of Independent States which have also not indicated whether they will attend, including Ukraine and Uzbekistan.

Saudi Arabia, OPEC and the Middle East

Saudi Arabia, with almost 1.2 percent of global emissions leads the list of the five OPEC nations and two other Middle Eastern states currently not confirmed to attend the event.

The country’s minister for Petroleum and Mineral Resources Ali Al-Naimi indicated in 2015 that Saudi Arabia would have to stop using fossil fuels at some point.

Despite this the country faced accusations of trying to wreck the climate deal at the Paris COP21 climate conference. The Guardian reported that Wael Hmaidan, director of Climate Action Network, said they were “undermining the position of other Arab countries.”

Meanwhile, Africa’s largest economy, Nigeria, is a major oil exporter and the second largest OPEC member who may not put pen to paper tomorrow. The country significantly out-emits the other African non-signatories, with 0.66 percent of global annual emissions.

Ecuador, one of the smallest OPEC members is the only South American country that hasn’t indicated it will sign.

Others include Iraq with more than 0.5 percent of global emissions, Qatar and non-OPEC countries Syria and Yemen, with emissions between 0.2 percent and 0.05 percent of the global total.

The Other No-Shows

According to the latest UN update there are still some sub-Saharan African countries that may not be at the New York ceremony. This includes Botswana and Zambia.

Last month, the think tank Third World Network called on developing nation to boycott the signing.

Speaking to ClimateHome on the call to boycott, an advisor to African nations said their slowing of the ratification process could lead to countries that stand to lose the most from climate change being excluded from talks on the deal’s implementation.

Others nations still missing from the list include Trinidad and Tobago and Nicaragua.

Michael Jacobs, visiting professor at the Grantham Research Institute on Climate Change told DeSmog UK that Russia, Saudi Arabia and other OPEC states will not like the rhetoric on decarbonization and the necessity of strong climate action which will surround the event. But it makes no difference.

Whether or not any of these countries show up on Friday, some 83 percent of states and 88 percent of emissions will still be represented at the ceremony.

And as Carbon Brief points out, the agreement is open for signatures at the UN headquarters for a year and that it’s even possible to accede to the agreement after this.

The next, more important step, is for those countries to get approval at home.

Once 55 percent of signatories covering 55 percent emissions do so, the agreement will come into effect after 30 days.

So far eight countries, Barbados, Belize, Fiji, The Maldives, Nauru, St Lucia, Samoa and Tuvalu have indicated they will deposit their instrument of ratification after the signing ceremony.

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By Kathleen Rogers

On April 22, 1970, 20 million Americans hit the streets to protest the environmental effects of more than 100 years of uncontrolled fossil-fueled industrial development. It was the first Earth Day.

What was intended to be a college campus teach-in soon spread to every community and city across the United States. It was and remains the single largest secular event in history. The sheer size of the protest—along with increasing visual evidence of dire health threats associated with air and toxic pollution—soon forced Congress to pass some of the world's toughest environmental laws, most of which include community right-to-know provisions and allow citizens to sue their government if it fails to enforce the law.

Citizens' rights have been enshrined in every major environmental law from that point on. These laws spawned others around the world—many more stringent than those in the U.S.—and most recognize the role of citizens in the enforcement of environmental laws.

Nearly 50 years later, Earth Day remains a day of reckoning, and now more than 1 billion people take action each year in almost every country on Earth. Some protest, many clean up their communities and plant trees, and millions more have their first exposure to environmentalism through educational programs at schools and universities. Governments large and small make commitments and meet with their constituents, while corporations make pledges to be more sustainable and responsible for the pollution they create.

It is fitting then that United Nations Secretary-General Ban Ki-moon chose Earth Day, April 22, for world leaders to sign the historic Paris climate agreement at UN headquarters in New York. At least 150 world leaders are expected to sign, making it the largest single signing of an international agreement in world history (another Earth Day first). And it's happening not a moment too soon. On every front, global warming is becoming more immediate, more threatening and more irreversible, while scientific consensus and data on the health effects of climate change—particularly on the poor—mount.

Critics warn that the agreement's specific emissions targets are too low, that the pace of implementation is too slow, and it fails failed to specify penalties for non-compliance. That's where we the people come in.

Included in the climate agreement are provisions that recognize the critical role civil society must play to make it work. It calls on citizens to scale up their efforts and support actions to reduce emissions. It signals the need for all of us to be actively engaged in transforming our world from one dominated by fossil fuels to one driven by renewable energy. While these words don't amount to a call for revolution, it's clear both the UN and world leaders recognize that citizen participation in solving global warming has been missing. The success—or failure—of the agreement is on our shoulders.

This isn't a fight in which any of us can remain on the sidelines and hope for the best. Unless we take these matters into our own hands, the agreement alone won't save the world's ecosystems from collapsing, or our biodiversity, which supports all living things on Earth, from disappearing.

Doing our part doesn't mean merely buying green products or inquiring how things are going. It means action. It means a direct challenge to the status quo. It means holding our elected officials accountable and voting out of office national, state and local leaders who won't take action on climate change. It means not passing the buck and hoping others do the hard work.

For many, getting involved means knowing how your retirement accounts and pensions are invested and demanding divestment from fossil fuel stocks. It means demanding that your children be educated for green jobs of the future. It means showing up at town hall or city council meetings and asking about your community's survivability in a climate crisis. It means saying “No" to every new coal or fracking project, and retooling those communities for safer green powered jobs.

And there are no doubt countless other ways to act. Undoubtable, the climate agreement makes it clear that governments don't have the power to solve climate change alone. We all must do something more than we currently are. Earth Day 2016 is not about crossing the finish line. When the agreement is signed, the hard work begins anew.

Kathleen Rogers is president of Earth Day Network.

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