Humans have caused climate change for 180 years- much earlier than thought from even small amounts of carbon emissions

August 24, 2016 Australian National University

An international research project has found human activity has been causing global warming for almost two centuries, proving human-induced climate change is not just a 20th century phenomenon….”…The climate warming we are witnessing today started about 180 years ago.” The new findings have important implications for assessing the extent that humans have caused the climate to move away from its pre-industrial state, and will help scientists understand the future impact of greenhouse gas emissions on the climate.

…The research, published in Nature, involved 25 scientists from across Australia, the United States, Europe and Asia, working together as part of the international Past Global Changes 2000 year (PAGES 2K) Consortium. Associate Professor Abram said anthropogenic climate change was generally talked about as a 20th century phenomenon because direct measurements of climate are rare before the 1900s.

…The data and simulations pinpointed the early onset of warming to around the 1830s, and found the early warming was attributed to rising greenhouse gas levels….humans only caused small increases in the level of greenhouse gases in the atmosphere during the 1800s. “But the early onset of warming detected in this study indicates the Earth’s climate did respond in a rapid and measureable way to even the small increase in carbon emissions during the start of the Industrial Age,” Dr McGregor said.

The researchers also studied major volcanic eruptions in the early 1800s and found they were only a minor factor in the early onset of climate warming.

Associate Professor Abram said the earliest signs of greenhouse-induced warming developed during the 1830s in the Arctic and in tropical oceans, followed soon after by Europe, Asia and North America. However, climate warming appears to have been delayed in the Antarctic, possibly due to the way ocean circulation is pushing warming waters to the North and away from the frozen continent.

Abram et al. Early onset of industrial-era warming across the oceans and continents. Nature, 2016; 536 (7617): 411 DOI: 10.1038/nature19082

Climate Change: Planetary Genetics vs Life Style Choices – Katharine Hayhoe

Katharine Hayhoe on Climate and our Choices- Short Video

Posted on 24 August 2016 by greenman3610

This is a re-post from Climate Denial Crock of the Week

I was fortunate to catch up with Katharine Hayhoe in June, while I was interviewing TV meteorologists at a conference in Austin, TX.  She was there to present and answer questions on the finer points of climate science for the assembled media mets.

Dr Hayhoe has been named one of Time Magazine’s most Influential People. She is a climate scientist working and teaching at Texas Tech University.

Rain bombs are coming to your town

Forget Tornadoes. Rain Bombs Are Coming for Your Town

Climate change is weaponizing the atmosphere.

Eric Roston eroston

July 29, 2016 — 3:00 AM PDT

Evidence shows that the sky is coming down on our heads—the watery part of it, anyway, in larger and larger cascades. It’s largely our own fault.

The past two months have seen some doozies just in the U.S. The Empire State Building was struck by lightning twice on Monday during a storm that brought an inch of rain down in what felt like a single sheet.

Last month, at least 23 people died in West Virginia flooding. At its peak on June 23, more than 8 inches to 10 inches fell within half a day—a once-every-1,000 years rain storm. Maelstroms in May and early June dropped five times as much rain as normal near Houston, seriously challenging the definition of normal. More than a dozen people died. It was the city’s fifth major flood in just over a year. (Rainfall is trending higher nationally, though paving over much of Texas probably doesn’t help.)

The most dramatic recent image came from Bruce Haffner, a Phoenix TV helicopter pilot, who snapped what looks very much like a 20-megaton warhead going off. This is informally known as a “rain bomb” (see article).

The phenomenon is known in meteorology circles as the more sober “wet microburst.” They are supposed to happen rarely; conditions must be just right. A thunderstorm runs into a dry patch of air that sucks some moisture away. The air underneath the storm cloud cools, making it more dense than the air around it. The cooler air begins to drop into even warmer air and then accelerates. When the faucet really flips on, air can blast out of the sky at more than 115 miles per hour. It deflects off the ground and pushes winds outward, at or near tornado strength. The Phoenix event above was actually a “macroburst,” with a radar footprint wider than about 2.5 miles, said Amber Sullins, chief meteorologist at ABC-15 News.

Scientists understand the mechanics of small-scale weather events such as rain bombs, tornadoes, and severe thunderstorms. The past few years have seen modest improvements in projections of how these storms might behave in a changing atmosphere, region-by-region.

“The research showing rain events for us being less frequent but more intense, due to climate change, seems to be our new reality,” Sullins said.

What’s known with much greater confidence by climatologists is that storms should continue to intensify. There’s little question that by stockpiling water vapor, the atmosphere is building a worldwide arsenal of “rain bombs”—or, if you like, wet microbursts, macrobursts, or just your typical, Noah-scale deluges. And unlike, say, the study of climate change and its relationship to war, why the sky keeps falling is clearer:

  • Human activity has increased the amount of carbon dioxide in the air by more than 40 percent above pre-industrial levels.

CA Assembly approves climate change law update – 40% reduction from 1990 levels by 2030

August 23, 2016 12:29 PM

The bill now requires a 40 percent reduction from 1990 levels by 2030. The current climate law, AB 32, required the state to reach 1990 levels by 2020.

Capitol Alert  By Anshu Siripurapu

After an intense floor debate, a bill extending California’s greenhouse gas emission targets squeaked by in the Assembly on Tuesday.

Senate Bill 32 was seen as a crucial step for reauthorizing the state’s cap-and-trade program. Gov. Jerry Brown attempted to include an amendment specifically extending cap-and-trade authority but was rebuffed by lawmakers.

The bill now requires a 40 percent reduction from 1990 levels by 2030. The current climate law, AB 32, required the state to reach 1990 levels by 2020.

“With SB 32 we continue California’s leadership on climate change,” said Assembly Speaker Anthony Rendon, D-Paramount. Rendon acknowledged that the bill does not expressly extend the cap-and-trade program, but said it was “a piece of the puzzle” and that he is committed to continuing the program.

The bill, which cleared the lower house 42-29 – one vote more than the 41-vote minimum – pitted the oil industry against environmentalists in heavy lobbying, is almost certain to be approved by the Senate.

The legislation gained passage wedded to a companion measure, Assembly Bill 197, to increase legislative oversight of the controversial California Air Resources Board.

Democratic lawmakers painted the climate package as necessary to wrest control of the state’s climate programs back from Gov. Jerry Brown’s administration….


California wildfires rage amidst remarkably inactive summer monsoon; ridiculously resilient ridge to return this winter in CA? Daniel Swain on August 23, 2016 • 13 Comments

Just how warm this summer has felt in California depends largely upon who you ask. Residents of immediate coastal Northern California–including most of the Bay Area–have benefited from nature’s air conditioning so far this season. Relatively cool ocean temperatures just offshore (a product of increased coastal upwelling this year) have resulted in a robust marine layer, and the traditional “June Gloom” associated with California’s marine stratus has persisted into August in some spots.

….Meanwhile, across all of Southern California and even more inland parts of Northern California, this summer has been yet another hot one–and several heatwaves have occurred since June. Unusually warm ocean conditions have persisted along the SoCal coastline, keeping the marine influence in check and allowing for very hot conditions at times just a few miles inland from the immediate coastline….

….During a typical summer, pulses of moist and relatively unstable air can move from east to west across the Desert Southwest in the clockwise flow around the 4-Corners High–sometimes triggering mountain and desert thunderstorms during the warm season. So far during summer 2016, though, this high pressure area has been centered almost directly over California. As a result, there have been remarkably few convectively active periods so far this season (although a handful of locations did fare a bit better over the past week).

…..The 4-Corners High has been stronger and more westward-shifted than usual this summer. (Daniel Swain via ESRL Plotter)…

….Interestingly (and somewhat disconcertingly), many of these fires have occurred despite the absence of strong and dry offshore wind events that often drive California’s most destructive fires. Instead, most of the current fires in California appear to be preferentially favoring those regions hardest hit in California’s ongoing, multi-year drought. Vegetation fuel moistures and “energy release components” (measures of flammability and potential combustion intensity, respectively) in these regions have reached or exceed record values this summer. While there is an increasing amount of evidence that California’s astonishing drought-related recent tree mortality may not directly increase wildfire intensity in the long run, it’s pretty clear that California’s severe drought has been exerting a strong influence upon fire risk and behavior across California over the past couple of years in other ways…..

….Is the probable lack of a moderate or strong La Niña during 2016-2017 good news for California? Well, it’s certainly true that a strong La Niña would probably be bad news for Southern California–which fared quite poorly precipitation-wise even during one of the strongest El Niño events on record last year. But as Californians have become painfully aware in recent years, La Niña is not the only possible cause of dry conditions and drought in California. The latest seasonal predictions–which are based upon simulations of an ensemble of ocean-atmosphere models that take into account the present state of the atmosphere, global oceans, and sea ice–do not inspire a great deal of hope that the coming winter will bring widespread drought relief. At the moment, these simulations depict a pattern characterized by persistent West Coast winter ridging. This setup looks a fair bit like the Ridiculously Resilient Ridge, and is similar to the kind of atmospheric ridge patterns we’ve started to see more frequently in recent decades…..


Historical documents reveal Arctic sea ice is disappearing at record speed

Posted on 22 August 2016 by dana1981

Walsh, J. E., Fetterer, F., Stewart, J. S. and Chapman, W. L. (2016) A database for depicting Arctic sea ice variations back to 1850. Geographical Review, doi:10.1111/j.1931-0846.2016.12195.x

Scientists have pieced together historical records to reconstruct Arctic sea ice extent over the past 125 years. The results are shown in the figure below. The red line, showing the extent at the end of the summer melt season, is the most critical:

Arctic sea ice extent in recent years is by far the lowest it’s been, with about half of the historical coverage gone, and the decline the fastest it’s been in recorded history. Florence Fetterer, principal investigator at the National Snow and Ice Data Center, described the data reconstruction process in a guest post at Carbon Brief….

….Most fundamentally of all, the new dataset allows us to answer the three questions we posed at the beginning of this article.

First, there is no point in the past 150 years where sea ice extent is as small as it has been in recent years. Second, the rate of sea ice retreat in recent years is also unprecedented in the historical record. And, third, the natural fluctuations in sea ice over multiple decades are generally smaller than the year-to-year variability.

A World at War—under attack from climate change—only hope to mobilize like WWII

We’re under attack from climate change—and our only hope is to mobilize like we did in WWII.

By Bill McKibben August 15, 2016 New Republic

In the North this summer, a devastating offensive is underway. Enemy forces have seized huge swaths of territory; with each passing week, another 22,000 square miles of Arctic ice disappears. Experts dispatched to the battlefield in July saw little cause for hope, especially since this siege is one of the oldest fronts in the war. “In 30 years, the area has shrunk approximately by half,” said a scientist who examined the onslaught. “There doesn’t seem anything able to stop this.”

In the Pacific this spring, the enemy staged a daring breakout across thousands of miles of ocean, waging a full-scale assault on the region’s coral reefs. In a matter of months, long stretches of formations like the Great Barrier Reef—dating back past the start of human civilization and visible from space—were reduced to white bone-yards.

Day after day, week after week, saboteurs behind our lines are unleashing a series of brilliant and overwhelming attacks. In the past few months alone, our foes have used a firestorm to force the total evacuation of a city of 90,000 in Canada, drought to ravage crops to the point where southern Africans are literally eating their seed corn, and floods to threaten the priceless repository of art in the Louvre. The enemy is even deploying biological weapons to spread psychological terror: The Zika virus, loaded like a bomb into a growing army of mosquitoes, has shrunk the heads of newborn babies across an entire continent; panicked health ministers in seven countries are now urging women not to get pregnant. And as in all conflicts, millions of refugees are fleeing the horrors of war, their numbers swelling daily as they’re forced to abandon their homes to escape famine and desolation and disease.

World War III is well and truly underway. And we are losing.

….Even if every nation in the world complies with the Paris Agreement, the world will heat up by as much as 3.5 degrees Celsius by 2100—not the 1.5 to 2 degrees promised in the pact’s preamble.

And it may be too late already to meet that stated target: We actually flirted with that 1.5 degree line at the height of the El Niño warming in February, a mere 60 days after the world’s governments solemnly pledged their best efforts to slow global warming.

…What would it mean to mobilize for World War III on the same scale as we did for the last world war?…

….In the past year, the Stanford team has offered similar plans for 139 nations around the world. The research delves deep into the specifics of converting to clean energy…

But would the Stanford plan be enough to slow global warming? Yes, says Jacobson: If we move quickly enough to meet the goal of 80 percent clean power by 2030, then the world’s carbon dioxide levels would fall below the relative safety of 350 parts per million by the end of the century. The planet would stop heating up, or at least the pace of that heating would slow substantially. That’s as close to winning this war as we could plausibly get. We’d endure lots of damage in the meantime, but not the civilization-scale destruction we currently face. (Even if all of the world’s nations meet the pledges they made in the Paris accord, carbon dioxide is currently on a path to hit 500 or 600 parts per million by century’s end—a path if not to hell, then to someplace with a similar setting on the thermostat.

…it’s important to remember that a truly global mobilization to defeat climate change wouldn’t wreck our economy or throw coal miners out of work. Quite the contrary: Gearing up to stop global warming would provide a host of social and economic benefits, just as World War II did. It would save lives…

Landscape adaptation can reduce impacts of climate change

16 Aug 2016, 1:22 p.m.

Increasing woody vegetation and reducing land use intensity could mitigate the impacts of climate change on insect biodiversity, according to new research by the University of New England, the NSW Office of Environment and Heritage, and the University of Melbourne.

Associate Professor Nigel Andrew from UNE’s School of Environmental and Rural Sciences says he and colleagues set out to assess how adapting landscapes can improve insect biodiversity conservation with a changing climate.

“We found that having more native trees and shrubs on a farm will enhance ant biodiversity and help mitigate the impacts of climate change. If you have a lot of exotic vegetation and bare ground, then many ant species will become more vulnerable to rapid change” said A/Prof Andrew.

Researchers sampled ant biodiversity across a 270-kilometre elevation gradient, west of Armidale, in New South Wales. The sites they sampled varied in vegetation cover and land-use.

A/Prof Andrew says 210-thousand arthropods were collected and sorted into major groups, and ants (making up 63% of the collection) were identified further to species level.

“There was greater ant richness associated with greater native woody plant canopy cover, while there was lower species richness with higher cultivation, grazing intensity and exotic plants.”

A/Prof Andrew says ant diversity is critical for the environment and landholders. “Ants dominate the environment we live in so if you lose ant species you can lose ecosystem functions. Ants collect seeds, aerate the soil and predate on pests. If you change the type of ants in an environment you can change the dynamics and ecology of your landscape. Once lost, the remaining species may not be as efficient at delivering function to the environment so the ecosystem can become less resilient to change.”

Researchers are using predictive modelling to help land managers see the impact that changing grazing intensity or the type of land cover, can have on ant richness.

“If you are able to modify land practises, if you want to build in resilience to environmental change on your farm then managing and increasing native vegetation is an important component: not only will it help in the health of the landscape but it will also help them become more adaptable to a warming climate.”

July- hottest month globally on record but some areas suffer more than others

World’s hottest month shows challenges global warming will bring

July was hotter than any month globally since records began – but some areas, such as the Middle East, suffer more than others

Emma Graham-Harrison Tuesday 16 August 2016 15.31 EDT Guardian UK Last modified on Tuesday 16 August 2016 18.07 EDT

In Siberia, melting permafrost released anthrax that had been frozen in a reindeer carcass for decades, starting a deadly outbreak. In Baghdad, soaring temperatures forced the government to shut down for days at a time. In Kuwait, thermometers hit a record 54C (129F).

July was the hottest month the world has endured since records began in 1880, scientists have said, and brought a painful taste of the troubles people around the world may have to grapple with as global warming intensifies. Results compiled by Nasa showed the month was 0.84C hotter than the 1951-1980 average for July, and 0.11C hotter than the previous record set in July 2015.

The temperature increase last month was not all due to climate change. Part of the increase came from the tail end of the El Niño phenomenon, which spreads warm water across the Pacific, giving a boost to global temperatures.

But scientists said the July record, which came after a string of new month-high temperatures, was particularly striking because it came as the impact of El Niño faded, and added weight to fears that 2016 will go down in history as the hottest year since records began.

“Even if we have it augmented by El Niño, it’s quite concerning as a citizen to see that we are flirting with very high numbers, and a record is a record,” said Jean-Noël Thepaut, head of Europe’s Copernicus climate change service.

He had not expected such a warm July, and said that although his organisation did not forecast temperatures, the high temperatures continued through the start of August and made a record for the year extremely likely. “What we can say over the last seven months is that every month has been a record; we are on good track to have another record year,” he said. Beyond immediate trends, longer-term weather patterns made clear the rise could not be dismissed as the impact of a severe El Niño, he said.

“One fact beyond what we are seeing today, among the last warmest years, 15 years have been obtained in the 21st century and we have not been in El Niño for 10 years. So there is a general longer-term trend,” Thepaut said….

Climate urgency: we’ve locked in up to 3 C global warming unless we reduce emissions and sequester carbon

Posted on 15 August 2016 by dana1981

While most people accept the reality of human-caused global warming, we tend not to view it as an urgent issue or high priority. That lack of immediate concern may in part stem from a lack of understanding that today’s pollution will heat the planet for centuries to come, as explained in this Denial101x lecture.

So far humans have caused about 1°C warming of global surface temperatures, but if we were to freeze the level of atmospheric carbon dioxide at today’s levels, the planet would continue warming. Over the coming decades, we’d see about another 0.5°C warming, largely due to what’s called the “thermal inertia” of the oceans (think of the long amount of time it takes to boil a kettle of water). The Earth’s surface would keep warming about another 1.5°C over the ensuing centuries as ice continued to melt, decreasing the planet’s reflectivity.

To put this in context, the international community agreed in last year’s Paris climate accords that we should limit climate change risks by keeping global warming below 2°C, and preferably closer to 1.5°C. Yet from the carbon pollution we’ve already put into the atmosphere, we’re committed to 1.5–3°C warming over the coming decades and centuries, and we continue to pump out over 30 billion tons of carbon dioxide every year.

The importance of reaching zero or negative emissions

We can solve this problem if, rather than holding the amount of atmospheric carbon dioxide steady, it falls over time. As discussed in the above video, Earth naturally absorbs more carbon than it releases, so if we reduce human emissions to zero, the level of atmospheric carbon dioxide will slowly decline. Humans can also help the process by finding ways to pull carbon out of the atmosphere and sequester it.

Scientists are researching various technologies to accomplish this, but we’ve already put over 500 billion tons of carbon dioxide into the atmosphere. Pulling a significant amount of that carbon out of the atmosphere and storing it safely will be a tremendous challenge, and we won’t be able to reduce the amount in the atmosphere until we first get our emissions close to zero.

There are an infinite number of potential carbon emissions pathways, but the 2014 IPCC report considered four possible paths that they called RCPs. In one of these (called RCP 2.6 or RCP3-PD), we take immediate, aggressive, global action to cut carbon pollution, atmospheric carbon dioxide levels peak at 443 ppm in 2050, and by 2100 they’ve fallen back down to today’s level of 400 ppm. In two others (RCPs 4.5 and 6.0) we act more slowly, and atmospheric levels don’t peak until the year 2150, then they remain steady, and in the last (RCP8.5) carbon dioxide levels keep rising until 2250.

As the figure below shows [see here], in the first scenario, global warming peaks at 2°C and then temperatures start to fall toward the 1.5°C level, meeting our Paris climate targets. In the other scenarios, temperatures keep rising centuries into the future.

This is the critical decade

We don’t know what technologies will be available in the future, but we do know that the more carbon pollution we pump into the atmosphere today, the longer it will take and more difficult it will be to reach zero emissions and stabilize the climate. We’ll also have to pull that much more carbon out of the atmosphere.

It’s possible that as in three of the IPCC scenarios, we’ll never get all the way down to zero or negative carbon emissions, in which case today’s pollution will keep heating the planet for centuries to come. Today’s carbon pollution will leave a legacy of climate change consequences that future generations may struggle with for the next thousand years.

Five years ago, the Australian government established a Climate Commission, which published a report discussing why we’re in the midst of the ‘critical decade’ on climate change:

Click here to read the rest