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Final call to save the world from ‘climate catastrophe’

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GLOBAL WARMING OF 1.5 °C – IPCC special report – Summary for Policymakers

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Review of the Draft Fourth National Climate Assessment

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Hong Kong feels the heat as Observatory issues second ‘very hot’ weather warning in October

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Hong Kong swelters in hottest October day for almost 130 years

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Melting Greenland ice now source of 25% of sea level rise, researchers say

Ocean levels rose 50 percent faster in 2014 than in 1993, with meltwater from the Greenland ice sheet now supplying 25 percent of total sea level increase compared with just 5 percent 20 years earlier, researchers reported Monday.

http://www.japantimes.co.jp/news/2017/06/27/world/science-health-world/melting-greenland-ice-now-source-25-sea-level-rise-researchers-say/#.WVWU6YiGOHs

The findings add to growing concern among scientists that the global watermark is climbing more rapidly than forecast only a few years ago, with potentially devastating consequences.

Hundreds of millions of people around the world live in low-lying deltas that are vulnerable, especially when rising seas are combined with land sinking due to depleted water tables, or a lack of ground-forming silt held back by dams.

Major coastal cities are also threatened, while some small island states are already laying plans for the day their drowning nations will no longer be livable.

“This result is important because the Intergovernmental Panel on Climate Change (IPCC)” — the U.N. science advisory body — “makes a very conservative projection of total sea level rise by the end of the century,” at 60 to 90 cm (24 to 35 inches), said Peter Wadhams, a professor of ocean physics at the University of Oxford who did not take part in the research.

That estimate, he added, assumes that the rate at which ocean levels rise will remain constant.

“Yet there is convincing evidence — including accelerating losses of mass from Greenland and Antarctica — that the rate is actually increasing, and increasing exponentially.”

Greenland alone contains enough frozen water to lift oceans by about 7 meters (23 feet), though experts disagree on the global warming threshold for irreversible melting, and how long that would take once set in motion.

“Most scientists now expect total rise to be well over a meter by the end of the century,” Wadhams said.

The new study, published in Nature Climate Change, reconciles for the first time two distinct measurements of sea level rise.

The first looked one-by-one at three contributions: ocean expansion due to warming, changes in the amount of water stored on land, and loss of land-based ice from glaciers and ice sheets in Greenland and Antarctica.

The second was from satellite altimetry, which gauges heights on the Earth’s surface from space.

The technique measures the time taken by a radar pulse to travel from a satellite antenna to the surface, and then back to a satellite receiver.

Up to now, altimetry data showed little change in sea levels over the last two decades, even if other measurements left little doubt that oceans were measurably deepening.

“We corrected for a small but significant bias in the first decade of the satellite record,” co-author Xuebin Zhang, a professor at Qingdao National Laboratory of Marine Science and Technology in China’s Shandong Province, told AFP.

Overall, the pace of global average sea level rise went up from about 2.2 mm a year in 1993, to 3.3 mm a year two decades later.

In the early 1990s, they found, thermal expansion accounted for fully half of the added millimeters. Two decades later, that figure was only 30 percent.

Andrew Shepherd, director of the Centre for Polar Observation and Modelling at the University of Leeds in England, urged caution in interpreting the results.

“Even with decades of measurements, it is hard to be sure whether there has been a steady acceleration in the rate of global sea level rise during the satellite era because the change is so small,” he said.

Disentangling single sources — such as the massive chunk of ice atop Greenland — is even harder.

But other researchers said the study should sound an alarm.

“This is a major warning about the dangers of a sea level rise that will continue for many centuries, even after global warming is stopped,” said Brian Hoskins, chair of the Grantham Institute at Imperial College London.

Trump has reheated debate with US withdrawal from Paris Agreement, former UN climate chief says

Speaking on sidelines of three-day World Sustainable Built Environment Conference in Hong Kong, Christiana Figueres insisted the global shift towards reducing carbon emissions would not be shaken.

The United Nations’ former climate chief has struck a defiant note against US President Donald Trump [1]’s pullout from the landmark Paris accord, insisting the global shift towards reducing carbon emissions will not be shaken.

In an interview with the Post, Christiana Figueres, who formerly headed the UN Framework Convention on Climate Change, even “thanked” Trump for effectively reinvigorating the discussion over global warming and making it headline news again. But she admitted it was sad to see the US give up its leading role.

“The announcement was a political message that Mr Trump wanted to give out, geared toward his political base,” said Figueres, who headed the negotiations leading to the Paris agreement in 2015 [3]

“Most of the US economy, most cities, states and corporations, will continue because they know its in their own interest.”

She was speaking on the sidelines of the three-day World Sustainable Built Environment Conference in Hong Kong on Monday, the city’s largest ever conference on sustainable buildings and urban development. Tackling climate change [4] in the face of rapid urbanisation is the key theme.

Trump’s politically-motivated gesture, Figueres said, would have limited impact on America, given that more than 175 US mayors, a growing number of states and more than 1,000 corporations had pledged to continue upholding commitments to the Paris Agreement.

“It is the White House which stepped out of [Paris], not the US economy,” she said. “That’s actually a sad statement to make as under normal conditions, a president should speak for the economy and the majority.”

Figueres brushed off Trump’s announcement as one riddled with inaccuracies, not least because there was no legal basis for it – no country can withdraw from the accord until three years after ratification – and his claims of bringing back coal industry jobs.

“It is not feasible and Mr Trump knows it,” she said, adding that most coal jobs had already been killed by cheap natural gas as a result of the recent shale revolution, and mining jobs had been taken over by mechanisation and automation.

“It will be increasingly difficult for other heads of state to take Mr Trump seriously,” she added, suggesting that Trump had undermined his country’s credibility.

Figueres said it would be inevitable that China – the world’s biggest carbon emitter – continued the charge as its leaders recognised decarbonisation was “good for their economy”.

Figueres, who now vice-chairs the Covenant of Mayors for Climate and Energy, said built-up environments contributed to one-fifth of global emissions. The conference was being held in Hong Kong as it was a gateway to Asia, she said.

“Asia marks whether the world is going to succeed in climate change actions or not.”

Tobacco To Fossil Fuels: Tracing the Roots of Trump’s Claims on Paris Climate Deal

To understand why President Donald Trump pulled the United States out of the global Paris climate agreement, we might start by looking at the sources he relied on to justify his decision.

https://www.desmogblog.com/2017/06/01/tobacco-fossil-fuels-tracing-roots-trump-s-claims-paris-climate-deal

But we’re not going to start there, but we will end there.

Instead, let’s go back to the early 1990s. The tobacco industry was facing multiple bans on advertising its products in countries around the world.

So the tobacco industry took ownership of a study that reviewed a bunch of other studies about the claimed impacts of tobacco advertising on actual tobacco consumption.

In short, the study, handed to Phillip Morris International, concluded there was no real link between tobacco advertising and smoking levels. Studies that had found a link were probably flawed, the report claimed.

The reports, the letters, and the memos back and forth, are all buried away in the Tobacco Industry Documents Archive at the University of California – San Francisco.

Clearly, the report would help the tobacco industry to argue there was no need to regulate the advertising of its products, because that advertising didn’t make a difference to smoking levels one way or the other.

National Economic Research Associates

The company that carried out that tobacco study was National Economic Research Associates.

Why is this relevant to Donald Trump and his decision to pull out of the Paris climate agreement?

When Trump spoke of the “onerous energy restrictions” he claimed the Paris deal placed on the United States, he cited figures from a report by the very same National Economic Research Associates (NERA).

According to the NERA study, the Paris agreement would cut coal and gas production, and “cost” America 2.7 million jobs.

Fossil Fuel Interests

Two groups, namely the American Council for Capital Formation (ACCF) and the U.S Chamber of Commerce, sponsored the NERA report (incidentally, a New York Times investigation described the chamber as Big Tobacco’s Staunch Friend in Washington, due to its advocacy for the industry).

NERA has also produced reports supporting the LNG industry and the coal industry.

The ACCF has, over the years, accepted funds from a string of major corporations and industry groups, including ExxonMobil, the American Petroleum Institute and foundations linked to the billionaire petrochemical brothers Charles and David Koch.

As a fact check by the Associated Press on the part of Trump’s speech citing the NERA study published points out:

“The study makes worst-case assumptions that may inflate the cost of meeting U.S. targets under the Paris accord while largely ignoring the economic benefits to U.S. businesses from building and operating renewable energy projects.

Academic studies have found that increased environmental regulation doesn’t actually have much impact on employment. Jobs lost at polluting companies tend to be offset by new jobs in green technology.”

A separate team of economists and scientists has also checked the claims made in the NERA report, which has previously been cited by failed Republican Presidential candidate (and climate science denier) Ted Cruz. They come to similarly unflattering conclusions to the AP fact check.

So in the end, we have President Trump relying on a questionable report paid for by groups with a clear vested interest in undermining the Paris agreement.

Cigarette, Anyone?

When reporters were being briefed in the hours before Trump walked out to the White House Rose Garden, it was Trump’s energy aide Mike Catanzaro making the calls.

As DeSmog’s Steve Horn has pointed out, Catanzaro is a former fossil fuel and energy lobbyist with a history of attacking climate science.

He also spent time working with Senator James Inhofe – the Republican who claims global warming is the greatest hoax ever. Catanzaro is just one of a parade of former industry lobbyists now in top positions in the Trump administration.

The Paris climate deal, struck in late 2015, was rightly declared a historic moment.

No doubt too, Trump’s declaration that he will join Nicaragua and Syria outside the deal will also be seen as historic.

It was a decision to delay action to regulate an industry, based on tired old propaganda techniques and the self-serving analysis of a polluting industry under attack.

Cigarette, anyone?

Fasten your seat belts: Climate change could add to turbulence during air travel

Flight turbulence could increase significantly under climate change, a study warns, potentially upping the risk of injury — or at least flight anxiety — for future airline passengers. Furthermore, fuel and maintenance costs for carriers could rise.

http://www.bendbulletin.com/nation/5214806-151/fasten-your-seat-belts-climate-change-could-add

An increase in atmospheric carbon dioxide concentrations could cause changes in the jet stream over the North Atlantic flight corridor, leading to a spike in air turbulence, suggests the research conducted by atmospheric scientist Paul Williams of the University of Reading.

By the middle of the century, with no effort to reduce atmospheric concentrations of carbon dioxide, the volume of airspace experiencing light turbulence would increase by about 59 percent.

Airspace experiencing severe turbulence could increase by anywhere from 36 percent to 188 percent, the study found.

“We’re particularly interested in severe turbulence, because that’s the kind of turbulence that’s strong enough to hospitalize people,” Williams told The Washington Post.

Forecasting algorithms can help pilots anticipate and avoid turbulent patches. But the research does suggest that future fliers could be in for a bumpier ride.

The paper builds on a 2013 study in the journal Nature Climate Change by Williams and colleague Manoj Joshi of the University of East Anglia, which found an increase in moderate-to-severe turbulence in the North Atlantic as a result of climate change.

The study did not investigate the effects on lighter or more severe degrees of turbulence. In the new paper, Williams expanded the study to light turbulence, and more severe conditions.

Light turbulence typically comes with only minor discomfort for passengers, perhaps an increase in nausea or anxiety. Severe turbulence has been known to cause injuries and even hospitalizations.

Williams focused on an area in the North Atlantic known for heavy air traffic, particularly between Europe and North America, and limited his simulations to winter, when turbulence is known to be at its highest.

He examined 21 different wind-related characteristics known to be indicators of air turbulence levels, including wind speed and changes in air flow direction.

The study found an increase in turbulence across the spectrum. Light turbulence was projected to increase by an average of 59 percent, light-to-moderate by 75 percent, moderate by 94 percent, moderate-to-severe by 127 percent and severe by 149 percent, although there’s substantial uncertainty associated with the more severe categories.

Williams stressed that severe turbulence would remain rare — even with the increase. But even an increase in light turbulence can cause greater wear and tear on planes or force pilots to use extra fuel redirecting their flight paths to avoid rough patches.

The increase in air turbulence may apply only to the North Atlantic, researchers not involved in the study said.

“Regional variations of this increase may be quite uncertain, particularly in the higher latitudes where other aspects of circulation change that are less well understood and more model-dependent may dominate,” said Isla Simpson, a scientist at the National Center for Atmospheric Research, in an emailed comment to The Post.

Kristopher Karnauskas, an atmospheric and oceanic sciences expert at the University of Colorado at Boulder, said the behavior of the jet stream over the Pacific may respond differently to climate change.

The study builds on an area of climate science that increasingly suggests rising global temperatures can cause changes in atmospheric airflow, including shifts in major air currents known as jet streams.

Because the equator is the warmest part of the planet, and warm air takes up more space than cold air, the atmosphere tends to be thicker around the center of Earth than at the poles. As a result, there’s a kind of downhill atmospheric slope from the equator to the poles over which air flows. While this is happening, Earth is constantly spinning, pushing airflow eastward. In the North Atlantic, the result is a jet stream — a meandering, wavy current flowing around the planet from west to east.

As the planet grows hotter, however, warming air near the surface could bring about changes in the atmospheric slope between equator and poles. Models such as the one used in Williams’ new paper have suggested that the jet stream could become stronger as a result, bringing about an increase in the types of wind patterns that lead to increased air turbulence.

Some research has already begun to detect changes in large-scale atmospheric currents. Other scientists have suggested that rapid warming in the Arctic is actually causing the jet stream to weaken.

There remains considerable uncertainty about how airflow near Earth’s surface might change in the future, Simpson said. But she said scientists are becoming more confident about the changes “that we expect to happen higher up, near the altitude where planes fly.”

Examining these issues can lead to a better understanding of the effects of climate change on aviation, Karnauskas said.

“I think it’s been decades that all of the attention has been on the impact of such industries like aviation on climate, but this is something that’s flipping it around and looking at the impact of climate on aviation,” he said. “If we can really understand the two-way street that we’re dealing with, that’s really going to help us understand ultimately how the climate will change in the future as a coupled system between the people and the atmosphere.”

Combined effect of brighter sun and CO₂ emissions could lead to unprecedented warming

The same carbon concentrations will cause more warming in future than in previous periods of high carbon dioxide due to the sun becoming stronger, experts warn

http://www.independent.co.uk/environment/co-sun-emissions-global-warming-a7667401.html

Carbon dioxide concentrations are heading towards values not seen in the past 200 million years. The sun has also been gradually getting stronger over time. Put together, these facts mean the climate may be heading towards warmth not seen in the past half a billion years.

A lot has happened on Earth since 500,000,000BC. Continents, oceans and mountain ranges have come and gone, and complex life has evolved and moved from the oceans onto the land and into the air. Most of these changes occur on very long timescales of millions of years or more. However, over the past 150 years global temperatures have increased by about 1°C, ice caps and glaciers have retreated, polar sea ice has melted, and sea levels have risen.

Some will point out that Earth’s climate has undergone similar changes before. So what’s the big deal this time?

Scientists can seek to understand past climates by looking at the evidence locked away in rocks, sediments and fossils. What this tells us is that yes, the climate has changed in the past, but the current speed of change is highly unusual. For instance, carbon dioxide hasn’t been added to the atmosphere as rapidly as today for at least the past 66m years.

In fact, if we continue on our current path and exploit all convention fossil fuels, then as well as the rate of CO₂ emissions, the absolute climate warming is also likely to be unprecedented in at least the past 420m years. That’s according to a new study we have published in Nature Communications.

In terms of geological time, 1°C of global warming isn’t particularly unusual. For much of its history the planet was significantly warmer than today, and in fact more often than not Earth was in what is termed a “greenhouse” climate state. During the last greenhouse state 50m years ago, global average temperatures were 10-15°C warmer than today, the polar regions were ice-free, palm trees grew on the coast of Antarctica, and alligators and turtles wallowed in swamp-forests in what is now the frozen Canadian Arctic.

In contrast, despite our current warming, we are still technically in an “icehouse” climate state, which simply means there is ice on both poles. The Earth has naturally cycled between these two climate states every 300m years or so.

Just prior to the industrial revolution, for every million molecules in the atmosphere, about 280 of them were CO₂ molecules (280 parts per million, or ppm). Today, due primarily to the burning of fossil fuels, concentrations are about 400 ppm. In the absence of any efforts to curtail our emissions, burning of conventional fossil fuels will cause CO₂ concentrations to be around 2,000ppm by the year 2250.

This is of course a lot of CO₂, but the geological record tells us that the Earth has experienced similar concentrations several times in the past. For instance, our new compilation of data shows that during the Triassic, around 200m years ago, when dinosaurs first evolved, Earth had a greenhouse climate state with atmospheric CO₂ around 2,000-3,000ppm.

High concentrations of carbon dioxide don’t necessarily make the world totally uninhabitable: the dinosaurs thrived, after all.

But that doesn’t mean this is no big deal. For a start, there is no doubt that humanity will face major socio-economic challenges dealing with the dramatic and rapid climate change that will result from the rapid rise to 2,000 or more ppm.

But our new study also shows that the same carbon concentrations will cause more warming in future than in previous periods of high carbon dioxide. This is because the Earth’s temperature does not just depend on the level of CO₂ (or other greenhouse gases) in the atmosphere. All our energy ultimately comes from the sun, and due to the way the sun generates energy through nuclear fusion of hydrogen into helium, its brightness has increased over time. Four and a half billion years ago when the Earth was young the sun was around 30 per cent less bright.

What really matters is the combined effect of the sun’s changing strength and the varying greenhouse effect. Looking through geological history we generally found that as the sun became stronger through time, atmospheric CO₂ gradually decreased. On average, both changes cancelled each other out.

But what about in the future? We found no past time period when the drivers of climate, or climate forcing, was as high as it will be in the future if we burn all the readily available fossil fuel. Nothing like it has been recorded in the rock record for at least 420m years.

A central pillar of geological science is the uniformitarian principle: that “the present is the key to the past”. If we carry on burning fossil fuels as we are at present, by 2250 this old adage is sadly no longer likely to be true. It is doubtful that this high-CO₂ future will have a counterpart, even in the vastness of the geological record.

Gavin Foster is a professor of isotope geochemistry at the University of Southampton, Dana Royer is a professor of earth and environmental sciences at Wesleyan University and Dan Lunt is a professor of climate science at the University of Bristol. This article first appeared on The Conversation (theconversation.com)