Download Global Warming--Milman et al.

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[7 short articles on climate change count as 1 for RDPs &
Rdgs. Notes Sheets]
Nasa: Earth is warming at a pace
'unprecedented in 1,000 years'
Oliver Milman
https://www.theguardian.com/environment/2016/aug/30/nasa-climate-change-warning-earthtemperature-warming
30 August 2016
The planet is warming at a pace not experienced within the past 1,000 years, at least,
making it “very unlikely” that the world will stay within a crucial temperature limit agreed
by nations just last year, according to Nasa’s top climate scientist.
This year has already seen scorching heat around the world, with the average global
temperature peaking at 1.38C above levels experienced in the 19th century, perilously close
to the 1.5C limit agreed in the landmark Paris climate accord. July was the warmest month
since modern record keeping began in 1880, with each month since October 2015 setting a new
high mark for heat.
But Nasa said that records of temperature that go back far further, taken via analysis of ice
cores and sediments, suggest that the warming of recent decades is out of step with any
period over the past millennium.
“In the last 30 years we’ve really moved into exceptional territory,” Gavin Schmidt,
director of Nasa’s Goddard Institute for Space Studies, said. “It’s unprecedented in 1,000
years. There’s no period that has the trend seen in the 20th century in terms of the inclination (of
temperatures).”
“Maintaining temperatures below the 1.5C guardrail requires significant and very rapid cuts
in carbon dioxide emissions or co-ordinated geo-engineering. That is very unlikely. We are not
even yet making emissions cuts commensurate with keeping warming below 2C.”
Schmidt repeated his previous prediction that there is a 99% chance that 2016 will be the
warmest year on record, with around 20% of the heat attributed to a strong El Niño climatic
event. Last year is currently the warmest year on record, itself beating a landmark set in 2014.
“It’s the long-term trend we have to worry about though and there’s no evidence it’s going
away and lots of reasons to think it’s here to stay,” Schmidt said. “There’s no pause or hiatus in
temperature increase. People who think this is over are viewing the world through rose-tinted
spectacles. This is a chronic problem for society for the next 100 years.”
Schmidt is the highest-profile scientist to effectively write-off the 1.5C target, which was
adopted at December’s UN summit after heavy lobbying from island nations that risk being
inundated by rising seas if temperatures exceed this level. Recent research found that just five
more years of carbon dioxide emissions at current levels will virtually wipe out any chance
of restraining temperatures to a 1.5C increase and avoid runaway climate change.
Temperature reconstructions by Nasa, using work from its sister agency the National Oceanic
and Atmospheric Administration, found that the global temperature typically rose by between
4-7C over a period of 5,000 years as the world moved out of ice ages. The temperature rise
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clocked up over the past century is around 10 times faster than this previous rate of
warming….[Dunn cut rest]
Earth’s Most Famous Climate Scientist Issues
Bombshell Sea Level Warning
By Eric Holthaus
July 20, 2015
http://www.slate.com/blogs/the_slatest/2015/07/20/sea_level_study_james_hansen_issues_dire_clim
ate_warning.html?wpsrc=sh_all_dt_tw_top
In what may prove to be a turning point for political action on climate change, a breathtaking
new study casts extreme doubt about the near-term stability of global sea levels.
The study—written by James Hansen, NASA’s former lead climate scientist, and 16 coauthors, many of whom are considered among the top in their fields—concludes that glaciers in
Greenland and Antarctica will melt 10 times faster than previous consensus estimates, resulting
in sea level rise of at least 10 feet in as little as 50 years. The study, which has not yet been peerreviewed, brings new importance to a feedback loop in the ocean near Antarctica that results in
cooler freshwater from melting glaciers forcing warmer, saltier water underneath the ice sheets,
speeding up the melting rate. Hansen, who is known for being alarmist and also right,
acknowledges that his study implies change far beyond previous consensus estimates. In a
conference call with reporters, he said he hoped the new findings would be “substantially more
persuasive than anything previously published.” I certainly find them to be.
To come to their findings, the authors used a mixture of paleoclimate records, computer models,
and observations of current rates of sea level rise, but “the real world is moving somewhat faster than
the model,” Hansen says.
Hansen’s study does not attempt to predict the precise timing of the feedback loop, only
that it is “likely” to occur this century. The implications are mindboggling: In the study’s likely
scenario, New York City—and every other coastal city on the planet—may only have a few
more decades of habitability left. That dire prediction, in Hansen’s view, requires “emergency
cooperation among nations.”
We conclude that continued high emissions will make multi-meter sea level rise practically
unavoidable and likely to occur this century. Social disruption and economic consequences of such
large sea level rise could be devastating. It is not difficult to imagine that conflicts arising from
forced migrations and economic collapse might make the planet ungovernable, threatening the
fabric of civilization.
The science of ice melt rates is advancing so fast, scientists have generally been reluctant to
put a number to what is essentially an unpredictable, nonlinear response of ice sheets to a
steadily warming ocean. With Hansen’s new study, that changes in a dramatic way. One of the
study’s co-authors is Eric Rignot, whose own study last year found that glacial melt from West
Antarctica now appears to be “unstoppable.” Chris Mooney, writing for Mother Jones, called that
study a “holy shit” moment for the climate.
One necessary note of caution: Hansen’s study comes via a nontraditional publishing
decision by its authors. The study will be published in Atmospheric Chemistry and Physics, an
open-access “discussion” journal, and will not have formal peer review prior to its appearance
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online later this week. The complete discussion draft circulated to journalists was 66 pages
long, and included more than 300 references. The peer review will take place in real time, with
responses to the work by other scientists also published online. Hansen said this publishing
timeline was necessary to make the work public as soon as possible before global negotiators
meet in Paris later this year. … [Dunn cut rest for space reasons]
U.N. Panel Issues Its Starkest Warning Yet on
Global Warming
By JUSTIN GILLIS
New York Times
http://www.nytimes.com/2014/11/03/world/europe/global-warming-un-intergovernmentalpanel-on-climate-change.html
NOV. 2, 2014
COPENHAGEN — The gathering risks of climate change are so profound that they could stall
or even reverse generations of progress against poverty and hunger if greenhouse emissions
continue at a runaway pace, according to a major new United Nations report.
Despite growing efforts in many countries to tackle the problem, the global situation is
becoming more acute as developing countries join the West in burning huge amounts of
fossil fuels, the Intergovernmental Panel on Climate Change said here on Sunday.
Failure to reduce emissions, the group of scientists and other experts found, could
threaten society with food shortages, refugee crises, the flooding of major cities and entire
island nations, mass extinction of plants and animals, and a climate so drastically altered it
might become dangerous for people to work or play outside during the hottest times of the
year.
“Continued emission of greenhouse gases will cause further warming and long-lasting
changes in all components of the climate system, increasing the likelihood of severe, pervasive
and irreversible impacts for people and ecosystems,” the report found.
In the starkest language it has ever used, the expert panel made clear how far society remains
from having any serious policy to limit global warming.
Doing so would require leaving the vast majority of the world’s reserves of fossil fuels
in the ground or, alternatively, developing methods to capture and bury the emissions
resulting from their use, the group said.
If governments are to meet their own stated goal of limiting the warming of the planet
to no more than 3.6 degrees Fahrenheit, or 2 degrees Celsius, above the preindustrial level,
they must restrict emissions from additional fossil-fuel burning to about 1 trillion tons of
carbon dioxide, the panel said. At current growth rates, that budget is likely to be
exhausted in something like 30 years, possibly less.
Yet energy companies have booked coal and petroleum reserves equal to several times
that amount, and they are spending some $600 billion a year to find more. Utilities and oil
companies continue to build coal-fired power plants and refineries, and governments are
spending another $600 billion or so directly subsidizing the consumption of
fossil fuels.
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By contrast, the report found, less than $400 billion a year is being spent around the
world to reduce emissions or otherwise cope with climate change. That is a small fraction of
the revenue spent on fossil fuels — it is less, for example, than the revenue of a single
American oil company, ExxonMobil.
The new report comes just a month before international delegates convene in Lima, Peru, to
devise a new global agreement to limit emissions, and it makes clear the urgency of their task.
Appearing Sunday morning at a news conference in Copenhagen to unveil the report, the
United Nations secretary general, Ban Ki-moon, appealed for strong action in Lima.
“Science has spoken. There is no ambiguity in their message,” Mr. Ban said. “Leaders
must act. Time is not on our side.”
Yet there has been no sign that national leaders are willing to discuss allocating the
trillion-ton emissions budget among countries, an approach that would confront the
problem head-on, but also raise deep questions of fairness…. [Dunn cut some for space
reasons]
The Intergovernmental Panel on Climate Change is a scientific body appointed by the
world’s governments to advise them on the causes and effects of global warming, and
potential solutions. The group, along with Al Gore, was awarded the Nobel Peace Prize in
2007 for its efforts to call attention to the climate crisis.
The new report is a 175-page synopsis of a much longer series of reports that the panel has
issued over the past year. It is the final step in a five-year effort by the body to analyze a vast
archive of published climate research….
A core finding of the new report is that climate change is no longer a distant threat, but
is being felt all over the world. “It’s here and now,” Rajendra K. Pachauri, the chairman of the
panel, said in an interview. “It’s not something in the future.”
The group cited mass die-offs of forests, such as those killed by heat-loving beetles in
the American West; the melting of land ice virtually everywhere in the world; an
accelerating rise of the seas that is leading to increased coastal flooding; and heat waves
that have devastated crops and killed tens of thousands of people…. [Dunn cut rest for space
reasons]
IPCC climate report: human impact is
'unequivocal'
UN secretary-general urges global response to clear message from scientists that climate change is
human-induced
Fiona Harvey in Stockholm
http://www.theguardian.com/environment/2013/sep/27/ipcc-climate-report-un-secretary-general
27 September 2013
World leaders must now respond to an "unequivocal" message from climate scientists and act with
policies to cut greenhouse gas emissions, the United Nations secretary-general urged on Friday.
Introducing a major report from a high level UN panel of climate scientists, Ban Ki-moon said, "The
heat is on. We must act."
In their starkest warning yet, following nearly seven years of new research on the climate, the
Intergovernmental Panel on Climate Change (IPCC) said it was "unequivocal" and that even if the world
begins to moderate greenhouse gas emissions, warming is likely to cross the critical threshold of 2C
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by the end of this century. That would have serious consequences, including sea level rises,
heatwaves and changes to rainfall meaning dry regions get less and already wet areas receive more.
In a crucial reinforcement of their message – included starkly in this report for the first time –
the IPCC warned that the world cannot afford to keep emitting carbon dioxide as it has been doing
in recent years. To avoid dangerous levels of climate change, beyond 2C, the world can only emit a
total of between 800 and 880 gigatonnes of carbon. Of this, about 530 gigatonnes had already been
emitted by 2011.
That has a clear implication for our fossil fuel consumption, meaning that humans cannot burn
all of the coal, oil and gas reserves that countries and companies possess. As the former UN
commissioner Mary Robinson told the Guardian last week, that will have "huge implications for social
and economic development." It will also be difficult for business interests to accept.
The central estimate is that warming is likely to exceed 2C, the threshold beyond which
scientists think global warming will start to wreak serious changes to the planet. That threshold is
likely to be reached even if we begin to cut global greenhouse gas emissions, which so far has not
happened, according to the report.
Other key points from the report are:
• Atmospheric concentrations of carbon dioxide, methane and nitrous oxide are now at levels
"unprecedented in at least the last 800,000 years."
• Since the 1950's it's "extremely likely" that human activities have been the dominant cause of
the temperature rise.
• Concentrations of CO2 and other greenhouse gases in the atmosphere have increased to levels that
are unprecedented in at least 800,000 years. The burning of fossil fuels is the main reason behind a 40%
increase in C02 concentrations since the industrial revolution.
• Global temperatures are likely to rise by 0.3C to 4.8C, by the end of the century depending
on how much governments control carbon emissions.
• Sea levels are expected to rise a further 26-82cm by the end of the century.
• The oceans have acidified as they have absorbed about a third of the carbon dioxide emitted.
Thomas Stocker, co-chair of the working group on physical science, said the message that greenhouse
gases must be reduced was clear. "We give very relevant guidance on the total amount of carbon that can't
be emitted to stay to 1.5 or 2C. We are not on the path that would lead us to respect that warming target
[which has been agreed by world governments]."
He said: "Continued emissions of greenhouse gases will cause further warming and changes in all
components of the climate system. Limiting climate change will require substantial and sustained
reductions of greenhouse gas emissions."
Though governments around the world have agreed to curb emissions, and at numerous
international meetings have reaffirmed their commitment to holding warming to below 2C by the
end of the century, greenhouse gas concentrations are still rising at record rates.
Rajendra Pachauri, chair of the IPCC, said it was for governments to take action based on the science
produced by the panel, consisting of thousands of pages of detail, drawing on the work of more than 800
scientists and hundreds of scientific papers.
"Heatwaves are very likely to occur more frequently and last longer. As the earth warms, we
expect to see currently wet regions receiving more rainfall, and dry regions receiving less, although
there will be exceptions," Stocker said.
Qin Dahe, also co-chair of the working group, said: "As the ocean warm, and glaciers and ice
sheets reduce, global mean sea level will continue to rise, but at a faster rate than we have
experienced over the past 40 years."
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The melting of Antarctica was already really bad.
It just got worse.
By Chris Mooney
http://www.washingtonpost.com/news/energy-environment/wp/2015/03/16/the-melting-of-antarcticawas-already-really-bad-it-just-got-worse/?tid=pm_business_pop
March 16, 2015
A hundred years from now, humans may remember 2014 as the year that we first learned that
we may have irreversibly destabilized the great ice sheet of West Antarctica, and thus set in
motion more than 10 feet of sea level rise.
Meanwhile, 2015 could be the year of the double whammy — when we learned the same about
one gigantic glacier of East Antarctica, which could set in motion roughly the same amount all over
again. Northern Hemisphere residents and Americans in particular should take note — when the bottom
of the world loses vast amounts of ice, those of us living closer to its top get more sea level rise than the
rest of the planet, thanks to the law of gravity.
The findings about East Antarctica emerge from a new paper just out in Nature Geoscience by an
international team of scientists representing the United States, Britain, France and Australia. They flew a
number of research flights over the Totten Glacier of East Antarctica — the fastest-thinning sector of the
world’s largest ice sheet — and took a variety of measurements to try to figure out the reasons behind its
retreat. And the news wasn’t good: It appears that Totten, too, is losing ice because warm ocean water is
getting underneath it.
“The idea of warm ocean water eroding the ice in West Antarctica, what we’re finding is that
may well be applicable in East Antarctica as well,” says Martin Siegert, a co-author of the study and
who is based at the Grantham Institute at Imperial College London.
That’s alarming, because the glacier holds back a much more vast catchment of ice that, were
its vulnerable parts to flow into the ocean, could produce a sea level rise of more than 11 feet —
which is comparable to the impact from a loss of the West Antarctica ice sheet. And that’s “a
conservative lower limit,” says lead study author Jamin Greenbaum, a PhD candidate at the University of
Texas at Austin…. [Dunn cut rest for space reasons]
Arctic Ice in Death Spiral
by Stephen Leahy
September 20, 2010 by Inter Press Service
http://ipsnews.net/news.asp?idnews=52896
UXBRIDGE, Canada - The carbon dioxide emissions from burning such fossil fuels have now
melted the Arctic sea ice to its lowest volume since before the rise of human civilisation and
dangerously upsetting the energy balance of the entire planet, climate scientists are reporting….
[Dunn cut some for space reasons]
There can be no recovery because tremendous amounts of extra heat are added every summer
to the region as more than 2.5 million square kilometres of the Arctic Ocean have been opened up
to the heat of the 24-hour summer sun. A warmer Arctic Ocean not only takes much longer to refreeze, it emits huge volumes of additional heat energy into the atmosphere, disrupting the weather
patterns of the northern hemisphere, scientists have now confirmed.
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"The exceptional cold and snowy winter of 2009-2010 in Europe, eastern Asia and eastern North
America is connected to unique physical processes in the Arctic," James Overland of the NOAA Pacific
Marine Environmental Laboratory in the United States told IPS in Oslo, Norway last June in an exclusive
interview. ' Paradoxically, a warmer Arctic means "future cold and snowy winters will be the rule
rather than the exception" in these regions, Overland told IPS.
There is growing evidence of widespread impacts from a warmer Arctic, agreed Serreze. "Trapping
all that additional heat has to have impacts and those will grow in the future," he said.
One local impact underway is a rapid warming of the coastal regions of the Arctic, where average
temperatures are now three to five degrees C warmer than they were 30 years ago… [Dunn cut for
Space reasons]
"I hate to say it but I think we are committed to a four- to six-degree warmer Arctic," Serreze said.
If the Arctic becomes six degrees warmer, then half of the world's permafrost will likely thaw,
probably to a depth of a few metres, releasing most of the carbon and methane accumulated there
over thousands of years, said Vladimir Romanovsky of the University of Alaska in Fairbanks and a
world expert on permafrost.
Methane is a global warming gas approximately 25 times more potent than carbon dioxide
(CO2).
That would be catastrophic for human civilisation, experts agree. The permafrost region spans 13
million square kilometres of the land in Alaska, Canada, Siberia and parts of Europe and contains at least
twice as much carbon as is currently present in the atmosphere - 1,672 gigatonnes of carbon, according a
paper published in Nature in 2009. That's three times more carbon than all of the worlds' forests contain.
A Canadian study in 2009 documented that the southernmost permafrost limit had retreated 130
kilometres over the past 50 years in Quebec's James Bay region. At the northern edge, for the first time in
a decade, the heat from the Arctic Ocean pushed far inland this summer, Romanovsky said.
There are no good estimates of how much CO2 and methane is being released by the thawing
permafrost or by the undersea permafrost that acts as a cap over unknown quantities of methane hydrates
(a type of frozen methane) along the Arctic Ocean shelf, he said… [Dunn cut rest]
Global warming: the final warning
According to yesterday's UN report, the world will be a much hotter place by 2100. This will be the impact ... [Note
these temperature degrees are Celsius; about 1.8 degree Fahrenheit /degree Celsius]
+2.4°: Coral reefs almost extinct
In North America, a new dust-bowl brings deserts to life in the high plains states, centred on Nebraska, but
also wipes out agriculture and cattle ranching as sand dunes appear across five US states, from Texas in the south
to Montana in the north.
Rising sea levels accelerate as the Greenland ice sheet tips into irreversible melt, submerging atoll nations and
low-lying deltas. In Peru, disappearing Andean glaciers mean 10 million people face water shortages. Warming
seas wipe out the Great Barrier Reef and make coral reefs virtually extinct throughout the tropics. Worldwide, a
third of all species on the planet face extinction
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+3.4°: Rainforest turns to desert
The Amazonian rainforest burns in a firestorm of catastrophic ferocity, covering South America with ash and
smoke. Once the smoke clears, the interior of Brazil has become desert, and huge amounts of extra carbon have
entered the atmosphere, further boosting global warming. The entire Arctic ice-cap disappears in the summer
months, leaving the North Pole ice-free for the first time in 3 million years. Polar bears, walruses and ringed seals
all go extinct. Water supplies run short in California as the Sierra Nevada snowpack melts away. Tens of millions
are displaced as the Kalahari desert expands across southern Africa
+4.4°: Melting ice caps displace millions
Rapidly-rising temperatures in the Arctic put Siberian permafrost in the melt zone, releasing vast quantities of
methane and CO2. Global temperatures keep on rising rapidly in consequence. Melting ice-caps and sea level rises
displace more than 100 million people, particularly in Bangladesh, the Nile Delta and Shanghai. Heatwaves and
drought make much of the sub-tropics uninhabitable: large-scale migration even takes place within Europe, where
deserts are growing in southern Spain, Italy and Greece. More than half of wild species are wiped out, in the worst
mass extinction since the end of the dinosaurs. Agriculture collapses in Australia
+5.4°: Sea levels rise by five metres
The West Antarctic ice sheet breaks up, eventually adding another five metres to global sea levels. If these
temperatures are sustained, the entire planet will become ice-free, and sea levels will be 70 metres higher than
today. South Asian society collapses due to the disappearance of glaciers in the Himalayas, drying up the Indus
river, while in east India and Bangladesh, monsoon floods threaten millions. Super-El Niños spark global weather
chaos. Most of humanity begins to seek refuge away from higher temperatures closer to the poles. Tens of millions
of refugees force their way into Scandanavia and the British Isles. World food supplies run out
+6.4°: Most of life is exterminated
Warming seas lead to the possible release of methane hydrates trapped in sub-oceanic sediments: methane
fireballs tear across the sky, causing further warming. The oceans lose their oxygen and turn stagnant, releasing
poisonous hydrogen sulphide gas and destroying the ozone layer. Deserts extend almost to the Arctic.
"Hypercanes" (hurricanes of unimaginable ferocity) circumnavigate the globe, causing flash floods which strip the
land of soil. Humanity reduced to a few survivors eking out a living in polar refuges. Most of life on Earth has been
snuffed out, as temperatures rise higher than for hundreds of millions of years.