the 2016 global heat record, a deadly heat wave in Southeast Asia, and “marine hot spots” that led to devastating coral bleaching could not have occurred without the influence of human-caused global warming.
we are manufacturing our own extremes according to scientists at the 2017 American Geophysical Union’s Annual Meeting in New Orleans
The reason we know this tipping point in extreme weather and climate events has been passed is because of a growing sub-field within climate science, known as detection and attribution research. Scientists who work in this field are the climate equivalent of CSI investigators, probing for clues about what may have led to an extreme event soon after it occurs. …
…..Scientists tend to shy away from bold pronouncements. But this year’s report is different…..On Wednesday, at the American Geophysical Union’s Annual Meeting in New Orleans, ….. contributors to 2016’s edition threw much of that typical caution to the increasingly gusty wind.
The message of the 2016 attribution issue is that a sea change has occurred in our understanding of what we, by burning fossil fuels for energy, are doing to our weather. In short, we’re now manufacturing our own extremes, scientists said.
It can no longer be said that we are simply raising the odds of particular events, or making them more severe, or both. In fact, we’re now pushing the climate into new territory entirely, researchers said.
In other words, instead of realizing the sci-fi fantasy of controlling our weather, we’ve done everything possible to push the atmosphere toward a new, more malevolent form of chaos.
Out of the 27 extreme events examined in the peer reviewed report, investigators looking into three of them — the 2016 global heat record, a deadly heat wave in Southeast Asia, and “marine hot spots” that led to devastating coral bleaching — concluded that the events could not have occurred without the influence of human-caused global warming. In other words, take away global warming, and these things probably wouldn’t have happened. …
…Regarding the 2016 global temperature record, scientists concluded that at least part of the warmth was due to a strong El Niño event, but that most of the warm temperature record was due to human-caused climate change during the past 100 years.
…Another study in the BAMS issue found that extreme heat in Southeast Asia, particularly India and Thailand, near the end of 2016 “would not have been possible without climate change.” ….
Under global climate change, Earth’s climatic zones will shift toward the poles. This is not just a future prediction; it is a trend that has already been observed in the past decades. The dry, semi-arid regions are expanding into higher latitudes, and temperate, rainy regions are migrating poleward. ….researchers provide new insight into this phenomenon by discovering that mid-latitude storms are steered further toward the poles in a warmer climate.
Their analysis, which also revealed the physical mechanisms controlling this phenomenon, involved a unique approach that traced the progression of low-pressure weather systems both from the outside — in their movement around the globe — and from the inside — analyzing the storms’ dynamics….
Talia Tamarin-Brodsky, Yohai Kaspi. Enhanced poleward propagation of storms under climate change. Nature Geoscience, 2017; DOI: 10.1038/s41561-017-0001-8
Several groups and individuals around the United States have gone to court to try to do what the Trump administration has so far declined to do: confront the causes and effects of global warming.
Efforts in the United States are part of a wave of litigation around the world, including a 2015 decision in which a court in the Netherlands ordered the Dutch government to toughen its climate policies; that case is under appeal. A 2017 report from the United Nations Environment Program found nearly 900 climate litigation suits in more than 20 countries.
…In California, two counties and a city recently sued 37 fossil fuel companies, seeking funds to cover the costs of dealing with a warming world. In Oregon, a federal lawsuit brought on behalf of young people is moving toward a February trial date, though the so-called children’s suit could be tossed out before that. And more than a dozen state attorneys general have sued to block Trump administration moves to roll back environmental regulations.
….In the new suits, Marin and San Mateo Counties and the City of Imperial Beach are accusing the oil companies of knowing that their industry would cause catastrophic climate change and covering up the evidence.
Serge Dedina, the mayor of Imperial Beach, said his community was already dealing with coastal flooding and increasingly heavy rains, and sees more to come as the sea level rises. “How do we make sure those responsible pay the costs so that residents of communities like mine don’t have to pay the costs?” he asked.
The supervisor for District 3 of Marin County, Kathrin Sears, said, “It’s time to hold these oil, gas and coal companies accountable for the damage they knew their products would cause.”
Now Mr. Pruitt heads the Environmental Protection Agency, and progressive attorneys general, especially New York’s Eric T. Schneiderman, are suing just as enthusiastically, along with environmental groups, to counter the administration’s efforts to roll back climate change regulations. …
Their pushback could already be having an effect. Last week, the Environmental Protection Agency reversed itself on a one-year delay it had announced on enforcing a rule regarding ozone — one day after attorneys general filed a lawsuit challenging the delay…
Climate change leads to loss of biodiversity worldwide. However, ecosystems with a higher biodiversity in the first place might be less affected a new study. Scientists found that when they experimentally warmed meadows, the diversity of nematode worms living in the soil went down in monocultures, whereas the opposite was true for meadows with many different herbaceous plant species.
…The last month was recorded as the warmest June ever in many parts of the world. Last year, 2016, was the warmest year in the modern temperature record. … poses direct threats to humans, like extreme weather events and global sea-level rise, but scientists are concerned that it may also affect our well-being indirectly via changes in biodiversity.…Today, ecologists are challenged by the question: what does a warmer world mean for biodiversity? More species, less species, or no change?…”The story is simple; you need biodiversity to conserve biodiversity in a warmer world.”
…The monoculture meadow created for the experiment resembled meadows found in intensively managed agricultural land. These new research findings therefore support conservationists who are advocating for maintaining species-rich ecosystems and farmland to sustain biodiversity, and thus human well-being, in a warmer world. This may help to prevent negative effects of climate warming, although likely with some limitations.
P. Thakur, D. Tilman, O. Purschke, M. Ciobanu, J. Cowles, F. Isbell, P. D. Wragg, N. Eisenhauer. Climate warming promotes not only species diversity but also taxonomic redundancy in complex environments. Sci. Adv., 2017 DOI: 10.1126/sciadv.1700866
Before 1990, oceans were rising at about 1.1 millimeters per year, or just 0.43 inches per decade. From 1993 through 2012, though, it finds that they rose at 3.1 millimeters per year, or 1.22 inches per decade.
A new scientific analysis finds that the Earth’s oceans are rising nearly three times as rapidly as they were throughout most of the 20th century, one of the strongest indications yet that a much feared trend of not just sea level rise, but its acceleration, is now underway. “We have a much stronger acceleration in sea level rise than formerly thought,” said Sönke Dangendorf, a researcher with the University of Siegen in Germany who led the study along with scientists at institutions in Spain, France, Norway and the Netherlands.
Their paper, just out in the Proceedings of the National Academy of Sciences, isn’t the first to find that the rate of rising seas is itself increasing — but it finds a bigger rate of increase than in past studies. The new paper concludes that before 1990, oceans were rising at about 1.1 millimeters per year, or just 0.43 inches per decade. From 1993 through 2012, though, it finds that they rose at 3.1 millimeters per year, or 1.22 inches per decade.
The cause, said Dangendorf, is that sea level rise throughout much of the 20th century was driven by the melting of land-based glaciers and the expansion of seawater as it warms, but sea level rise in the 21st century has now, on top of that, added in major contributions from the ice sheets of Greenland and Antarctica.
“The sea level rise is now three times as fast as before 1990,” Dangendorf said….Kopp added that in the past five years, there is some indication that sea level rise could already be even higher than the 3.1 millimeter annual rate seen from 1993 through 2012. He cautioned, though, that “those higher rates over a short period of time probably include some level of natural variability as well as continued, human-caused acceleration.”…“Sea levels will continue to rise over the coming century, no matter whether we will adapt or not, but I think we can limit at least a part of the sea level rise. It will further accelerate, but how much is related to how we act as humans,” Dangendorf said
Twila Moon is pictured during field work to study ice-ocean interaction at the LeConte Glacier, Alaska. Credit: Twila Moon/NSIDC
Glaciers around the world are disappearing before our eyes, and the implications for people are wide-ranging and troubling, Twila Moon, a glacier expert at the University of Colorado Boulder, concludes in a Perspectives piece in the journal Science today.
The melting of glacial ice contributes to sea-level rise, which threatens to “displace millions of people within the lifetime of many of today’s children,” Moon writes. Glaciers also serve up fresh water to communities around the world, are integral to the planet’s weather and climate systems, and they are “unique landscapes for contemplation or exploration.”
And they’re shrinking, fast, writes Moon, who returned to the National Snow and Ice Data Center this month after two years away. Her analysis, “Saying goodbye to glaciers,” is published in the May 12 issue of Science….
Global warming is responsible for a tripling in the frequency of extreme West African Sahel storms observed in just the last 35 years, an international team of experts has reported…
…climate change will see the Sahel experience many more instances of extreme rain in future… The findings — published in the journal Nature — note that further strengthening of intense storms in the Sahel known as Mesoscale Convective Systems (MCSs) will increase the risk of more frequent and severe flooding and disease due to poor sanitation in West African cities. …
…In 2009 a downpour of 263mm [10 inches] over several hours forced 150,000 residents of Ouagadougou, in Burkina Faso, to leave their homes….The research indicates that MCS intensification is linked to increasingly hot conditions in the Sahara desert resulting from human-made greenhouse gas emissions
Professor Taylor, said, “Global warming is expected to produce more intense storms, but we were shocked to see the speed of the changes taking place in this region of Africa.”…
Christopher M. Taylor, Danijel Belušić, Françoise Guichard, Douglas J. Parker, Théo Vischel, Olivier Bock, Phil P. Harris, Serge Janicot, Cornelia Klein, Gérémy Panthou. Frequency of extreme Sahelian storms tripled since 1982 in satellite observations. Nature, 2017; 544 (7651): 475 DOI: 10.1038/nature22069
Global warming is reshuffling the ranges of animals and plants around the world with profound consequences for humanity, according to a major new analysis. Rising temperatures on land and sea are increasingly forcing species to migrate to cooler climes, pushing disease-carrying insects into new areas, moving the pests that attack crops and shifting the pollinators that fertilise many of them, an international team of scientists has said.
They warn that some movements will damage important industries, such as forestry and tourism, and that tensions are emerging between nations over shifting natural resources, such as fish stocks. The mass migration of species now underway around the planet can also amplify climate change as, for example, darker vegetation grows to replace sun-reflecting snow fields in the Arctic.
“Human survival, for urban and rural communities, depends on other life on Earth,” the experts write in their analysis published in the journal Science. “Climate change is impelling a universal redistribution of life on Earth.”…
As the global climate changes, human well-being, ecosystem function, and even climate itself are increasingly affected by the shifting geography of life.
Climate-driven changes in species distributions, or range shifts, affect human well-being both directly (for example, through emerging diseases and changes in food supply) and indirectly (by degrading ecosystem health). Some range shifts even create feedbacks (positive or negative) on the climate system, altering the pace of climate change.
PHOTO CREDITS (CLOCKWISE FROM TOP): ISTOCK.COM/BORCHEE; ISTOCK.COM/JURGAR; ISTOCK.COM/ROMOLOTAVANI
Changing planet-scale air patters like the jet stream causes weather to become more stuck in place
Droughts, heat waves, rainfall and more may persist longer
by Chris Mooney, Energy & Environment, Washington Post, Mar 27, 2017
Ever since 2012, scientists have been debating a complex and frankly explosive idea about how a warming planet will alter our weather — one that, if it’s correct, would have profound implications across the Northern Hemisphere and especially in its middle latitudes, where hundreds of millions of people live.
The idea is that climate change doesn’t merely increase the overall likelihood of heat waves, say, or the volume of rainfall — it also changes the flow of weather itself. By altering massive planet-scale air patterns like the jet stream (pictured below), which flows in waves from west to east in the Northern Hemisphere, a warming planet causes our weather to become more stuck in place. This means that a given weather pattern, whatever it may be, may persist for longer, thus driving extreme droughts, heat waves, downpours and more.
Visualization of a very wavy Northern Hemisphere jet stream. (NASA)
This basic idea has sparked half a decade of criticism and debate, and at the cutting edge of research, scientists continue to grapple with it. And now, a new study once again reinforces one of its core aspects.
Publishing in Nature Scientific Reports, Michael Mann of Pennsylvania State University and a group of colleagues at research institutes in the United States, Germany and the Netherlands find that at least in the spring and summer, the large scale flow of the atmosphere is indeed changing in such a way as to cause weather to get stuck more often…
THE MEASURED warming of the planet is not hypothetical. Nor are its effects, which are happening now, not decades from now. An ecological catastrophe is unfolding off Australia’s coast: Humans are killing the Great Barrier Reef, one of the world’s greatest natural wonders, and there’s nothing Australians on their own can do about it. We are all responsible.
An ocean water temperature spike last year caused a massive “bleaching” event, in which colorful corals turned an antiseptic, sickly white. Scientists believe that the reef will never be the same.
“The chances of the northern Great Barrier Reef returning to its pre-bleaching assemblage structure are slim given the scale of damage that occurred in 2016 and the likelihood of a fourth bleaching event occurring within the next decade or two as global temperatures continue to rise,” a major new study in the journal Nature reported last week….
….Alarmingly, but perhaps not surprisingly, the Australian government reports that sections of the reef are getting slammed again this year….
…There is little doubt that temperature is the culprit. Reefs far away from human runoff and other local risks are suffering. Corals in pristine water bleached just like those in dirty water. The Nature study quantified a relationship between exposure to warm water and the severity of observed bleaching.
“Immediate global action to curb future warming is essential to secure a future for coral reefs,” the study warned. “Water quality and fishing pressure had minimal effect on the unprecedented bleaching in 2016, suggesting that local protection of reefs affords little or no resistance to extreme heat. Similarly, past exposure to bleaching in 1998 and 2002 did not lessen the severity of bleaching in 2016.”…