Scientific consensus: Earth's climate is warming

Scientific consensus: Earth's climate is warming:

 Most leading scientific organizations worldwide have issued public statements endorsing the position that climate-warming trends over the past century are extremely likely due to human activities.
Human influence on the climate system is clear, and recent anthropogenic emissions of greenhouse gases are the highest in history. Recent climate changes have had widespread impacts on human and natural systems

Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position. The following is a partial list of these organizations, along with links to their published statements and a selection of related resources.

Climate change is real. There will always be uncertainty in understanding a system as complex as the world’s climate. However there is now strong evidence that significant global warming is occurring. The evidence comes from direct measurements of rising surface air temperatures and subsurface ocean temperatures and from phenomena such as increases in average global sea levels, retreating glaciers, and changes to many physical and biological systems.

 It is likely that most of the warming in recent decades can be attributed to human activities

Statement on climate change from 18 scientific associations

"Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver." (2009)2

American Association for the Advancement of Science

"The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society." (2006)3

American Chemical Society

"Comprehensive scientific assessments of our current and potential future climates clearly indicate that climate change is real, largely attributable to emissions from human activities, and potentially a very serious problem." (2004)4

American Geophysical Union

"Human‐induced climate change requires urgent action. Humanity is the major influence on the global climate change observed over the past 50 years. Rapid societal responses can significantly lessen negative outcomes." (Adopted 2003, revised and reaffirmed 2007, 2012, 2013)5

American Medical Association

"Our AMA ... supports the findings of the Intergovernmental Panel on Climate Change’s fourth assessment report and concurs with the scientific consensus that the Earth is undergoing adverse global climate change and that anthropogenic contributions are significant." (2013)6

American Meteorological Society

"It is clear from extensive scientific evidence that the dominant cause of the rapid change in climate of the past half century is human-induced increases in the amount of atmospheric greenhouse gases, including carbon dioxide (CO2), chlorofluorocarbons, methane, and nitrous oxide." (2012)7

American Physical Society

"The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now." 

The Geological Society of America

"The Geological Society of America (GSA) concurs with assessments by the National Academies of Science (2005), the National Research Council (2006), and the Intergovernmental Panel on Climate Change (IPCC, 2007) that global climate has warmed and that human activities (mainly greenhouse‐gas emissions) account for most of the warming since the middle 1900s." (2006; revised 2010)9

U.S. National Academy of Sciences

"The scientific understanding of climate change is now sufficiently clear to justify taking steps to reduce the amount of greenhouse gases in the atmosphere." (2005)11

U.S. Global Change Research Program

"The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human 'fingerprints' also have been identified in many other aspects of the climate system, including changes in ocean heat content, precipitation, atmospheric moisture, and Arctic sea ice." (2009, 13 U.S. government departments and agencies)12

Intergovernmental Panel on Climate Change

“Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen.”13

The following page lists the nearly 200 worldwide scientific organizations that hold the position that climate change has been caused by human action.

http://opr.ca.gov/s_listoforganizations.php

U.S. agencies

The following page contains information on what federal agencies are doing to adapt to climate change.

http://www.c2es.org/docUploads/federal-agencies-adaptation.pdf

NOAA: March 2016 Was the Most Abnormally Warm Month on Record.

Data released on Thursday shows that March 2016 was the warmest March since at least 1891, making it the planet's 11th consecutive month to set a global temperature milestone. Scientists are witnessing the effects of climate change. The global average surface temperature in March was 0.62 degrees Celsius, or 1.16 degrees Fahrenheit, above the 1981-2010 average. When measured against the 20th century average, the month looks even more unusual, at 1.07 degrees Celsius, or 1.9 degrees Fahrenheit, above average. March 2016 follows the most two most unusually warm months on record, which occurred in January and February. 

NOAA reports that March 2016 Was the Most Abnormally Warm Month on Record For the Planet, ever.

Alaska, Canada, Greenland, Central Siberia, and the Urals all experienced the most abnormally warm March, with temperatures 4 to 6 degrees Celsius above the average. In the Arctic, Greenland commenced its melt season more than one month early with temperatures skyrocketing into 60 degrees Fahrenheit in southwest Greenland and breaking records all the way to the top of the ice sheet itself, more than 10,000 feet above sea level. 

Earth's global temperatures in March 2016 were the most abnormally warm on record for any month, according to NOAA. This is the second month in a row that this remarkable feat has occurred. March 2016 is also the eleventh consecutive month in a row that the earth has recorded its warmest respective month on record. In addition to NOAA, three other agencies confirmed that this past March was the warmest on record. The Japan Meteorological Agency (JMA) calculated the global mean March 2016 temperature was 0.62 degrees Celsius (about 1.1 degrees Fahrenheit) above the March 30-year average from 1981-2010. A second analysis from NASA's Goddard Institute for Space Studies also concluded March anomalies were the highest in their period of record dating to 1880, a whopping 1.28 degrees Celsius above the 1951-1980 average period. NASA found the March 2016 anomaly crushed the previous March record by over 0.3 degrees. NOAA's global State of the Climate report released Tuesday found March's temperature over the Earth's surface was 1.22 degrees Celsius above the 20th century average, not only crushing the warmest March in the 137-year period of record set just one year prior, but also the largest temperature anomaly of any month in NOAA's database dating to 1880.

Whether one looks at a 12-month running average, 5-year average, or 30-year trends, all show stark increases in global average surface temperatures, which scientists have concluded is largely attributable to human-caused greenhouse gas emissions from the burning of fossil fuels.

Greenland is experiencing a early spring thaw.

The 2012 melt season, according to the National Snow and Ice Data Center, experienced melting even at mountainous heights over a mile into the sky atop Greenland. “During a peak melt event in July, even the summit areas of the ice sheet, nearly two miles above sea level, saw snowmelt conditions,” the group wrote. “While this has been observed in ice cores a handful of times in the past 1,000 years, it had not previously occurred in this century.” That’s not normal. 

A vast region of Greenland is experiencing a freakishly early spring thaw. Summer-like temperatures—a balmy 10 degrees Celsius (50 degrees Fahrenheit)—have created a melt area encompassing 12 percent of the planet’s northernmost ice sheet, according to analysis by the Danish Meteorological Institute (DMI). 

Almost 12% of Greenland’s ice sheet was melting on Monday, according to data crunched by the Danish Meteorological Institute. It beat by almost a month the previous record for a melt of more than 10%, on 5 May 2010.

“We had to check that our models were still working properly,”6 Peter Langen, climate scientist at DMI, told blog Polar Portal. Temperature readings on the ice were in line with the numbers, however, exceeding 10C in some places. Even a weather station 1840 metres above sea level recorded a maximum of 3.1C, which data analysts said would be warm for July, let alone April. Greenland’s usual melt season runs from early June to September. “Too much. Too early,” tweeted the World Meteorological Organisation.

Widespread melting on the Greenland ice sheet typically doesn’t get going until May. In fact, the three earliest dates for a melt area exceeding 10 percent are May 5, 2010, May 8, 1990, and May 8, 2006. “It is a very unusual situation, especially so early in the year,” climate scientist Martin Stendel said in a blog post, adding that cold air and low pressure systems to the east and west of Greenland have forced a warm air “cap” over the island.

Researchers attributed the surprising early melt this year to weather conditions, and more specifically, a warm midlatitude air mass getting stuck over the ice sheet. “The strong south air flow onto Greenland has produced warm air, rain instead of snow, and melting of snow that is in Nuuk,” Greenland’s capital, Jason Box, a researcher with the Geological Survey of Denmark and Greenland, said by email. So, what’ll happen to all that meltwater swimming atop of the ice sheet this week? In all likelihood, temperatures will soon drop, and it’ll percolate into the snow and refreeze, meteorologist Ruth Mottram of the DMI told New Scientist. But by doing so, the meltwater will carry heat energy to lower depths, reducing the amount required to thaw the ice out later. And if past years are any indicator, Greenland is in for another hot, melty summer.

In other words, time to bust out your rain boots if you live in Miami.

Contribution of Antarctica to past and future sea-level rise.

Polar temperatures over the last several million years have, at times, been slightly warmer than today, yet global mean sea level has been 6–9 metres higher as recently as the Last Interglacial (130,000 to 115,000 years ago) and possibly higher during the Pliocene epoch (about three million years ago). In both cases the Antarctic ice sheet has been implicated as the primary contributor, hinting at its future vulnerability.

 Here we use a model coupling ice sheet and climate dynamics—including previously underappreciated processes linking atmospheric warming with hydrofracturing of buttressing ice shelves and structural collapse of marine-terminating ice cliffs—that is calibrated against Pliocene and Last Interglacial sea-level estimates and applied to future greenhouse gas emission scenarios. Antarctica has the potential to contribute more than a metre of sea-level rise by 2100 and more than 15 metres by 2500, if emissions continue unabated. In this case atmospheric warming will soon become the dominant driver of ice loss, but prolonged ocean warming will delay its recovery for thousands of years.

If we use numerical climate simulations, paleoclimate data, and modern observations to study the effect of growing ice melt from Antarctica and Greenland. 

 We hypothesize that ice mass loss from the most vulnerable ice, sufficient to raise sea level several meters, is better approximated as exponential than by a more linear response. Doubling times of 10, 20 or 40 years yield multi-meter sea level rise in about 50, 100 or 200 years. Recent ice melt doubling times are near the lower end of the 10–40-year range, but the record is too short to confirm the nature of the response. 

The feedbacks, including subsurface ocean warming, help explain paleoclimate data and point to a dominant Southern Ocean role in controlling atmospheric CO2, which in turn exercised tight control on global temperature and sea level. The millennial (500–2000-year) timescale of deep-ocean ventilation affects the timescale for natural CO2 change and thus the timescale for paleo-global climate, ice sheet, and sea level changes, but this paleo-millennial timescale should not be misinterpreted as the timescale for ice sheet response to a rapid, large, human-made climate forcing. These climate feedbacks aid interpretation of events late in the prior interglacial, when sea level rose to +6–9 m with evidence of extreme storms while Earth was less than 1 °C warmer than today. Ice melt cooling of the North Atlantic and Southern oceans increases atmospheric temperature gradients, eddy kinetic energy and baroclinicity, thus driving more powerful storms. The modeling, paleoclimate evidence, and ongoing observations together imply that 2 °C global warming above the preindustrial level could be dangerous. Continued high fossil fuel emissions this century are predicted to yield (1) cooling of the Southern Ocean, especially in the Western Hemisphere; (2) slowing of the Southern Ocean overturning circulation, warming of the ice shelves, and growing ice sheet mass loss; (3) slowdown and eventual shutdown of the Atlantic overturning circulation with cooling of the North Atlantic region; (4) increasingly powerful storms; and (5) nonlinearly growing sea level rise, reaching several meters over a timescale of 50–150 years. These predictions, especially the cooling in the Southern Ocean and North Atlantic with markedly reduced warming or even cooling in Europe, differ fundamentally from existing climate change assessments. We discuss observations and modeling studies needed to refute or clarify these assertions.

Meltwater tends to stabilize the ocean column, inducing amplifying feedbacks that increase subsurface ocean warming and ice shelf melting. Cold meltwater and induced dynamical effects cause ocean surface cooling in the Southern Ocean and North Atlantic, thus increasing Earth's energy imbalance and heat flux into most of the global ocean's surface. Southern Ocean surface cooling, while lower latitudes are warming, increases precipitation on the Southern Ocean, increasing ocean stratification, slowing deepwater formation, and increasing ice sheet mass loss. These feedbacks make ice sheets in contact with the ocean vulnerable to accelerating disintegration

What is happening in the Arctic now is unprecedented & possibly catastrophic.

"What is happening in the Arctic now is unprecedented & possibly catastrophic."

That is from a world-known scientist, Dr. Peter Gleick, who is a member of the US National Academy of Science, a MacArthur Fellow, and President of the Pacific Institute. 

This is not a "national crisis". This is a threat to life on this planet as we know it. I won't stop talking about it until we, and our leaders, start to realize how severe it is.

Do you think climate silence is a conspiracy by a few major media corporations - or is it possible that all of us are so addicted to fossil fuels, we really don't want to know? To be honest, I can barely bring myself to read the latest news. Maybe the problems in the Arctic are just too big to comprehend, or just too scary to face? Is it worthwhile to keep fighting, if all we can do is slow down the loss - and the damage, for the next generation? There is, says Gleick, a big difference between a civilization facing severe challenges as the Earth warms, and a planet where climate changes so far and so fast that civilization cannot cope or adapt. We'll have to make major efforts to adapt to what we have already done. We can't continue to make it worse.

Let's say Greenland ice loss doubles or triples, and the Arctic sea ice disappears for most of the year. Gleick agrees nobody knows what would happen. When we change the greenhouse gases in the atmosphere, we are running a giant experiment on the Earth. It's already out of control.

January Arctic sea ice extent was the lowest in the satellite record, attended by unusually high air temperatures over the Arctic Ocean. January 2016 was a remarkably warm month. Air temperatures were more than 6 degrees Celsius (13 degrees Fahrenheit) above average across most of the Arctic Ocean. The Arctic is absorbing a lot more solar energy, and at a much greater rate, than anywhere else on the planet. In the last number of decades, the Arctic temperature has risen 1.0C per decade whereas the global average temperature rise has been about 0.15C per decade. Arctic sea ice extent for February averaged 14.22 million square kilometers (5.48 million square miles), the lowest February extent in the satellite record. It is 1.16 million square kilometers (448,000 square miles) below the 1981 to 2010 long-term average of 15.4 million square kilometers (5.94 million square miles) and is 200,000 square kilometers (77,000 square miles) below the previous record low for the month recorded in 2005.

The first three weeks of February saw little ice growth, but extent rose during the last week of the month primarily due to growth in the Sea of Okhotsk (180,000 square kilometers or 70,000 square miles) and to a lesser extent in Baffin Bay (35,000 square kilometers or 13,500 square miles). Extent is presently below average in the Barents and Kara seas, as well as the Bering Sea and the East Greenland Sea. Extent decreased in the Barents and East Greenland seas during the month of February. In other regions, such as the Sea of Okhotsk, Baffin Bay, and the Labrador Sea, ice conditions are near average to slightly above average for this time of year. An exception is the Gulf of St. Lawrence, which remains largely ice free.

Cryosphere climate change is not like air or water pollution, where the impacts remain local and when addressed, allow ecosystems largely to recover. Cryosphere climate change, driven by the physical laws of water’s response to the freezing point, is different. Slow to manifest itself, once triggered it inevitably forces the Earth’s climate system into a new state, one that most scientists believe has not existed for 35–50 million years. Adaptation to the levels of projected climate-related disruption, particularly sea-level rise that cannot be halted and accelerates over the centuries, simply will not be possible without massive migration and other changes to human centers of population and infrastructure, that will carry enormous economic and not least, historic and cultural costs. The only way fully to avoid these risks is never to let temperatures rise into these risk zones. After the climate is broken, and the cryosphere starts it's unstoppable melt, there is no way to "fix" it. Basically: humans will have to leave their coastal cities behind, and the some of the most fertile near-ocean river estuaries that now support many millions of people.

Here is what the ICCI says in a summary about this report:

"Policy makers and the general public alike now largely accept that the Arctic, Antarctica and many mountain regions already have warmed two-three times faster than the rest of the planet. What is less understood, outside the scientific community, is that the very nature of the cryosphere – regions of snow and ice – carries dynamics that once triggered, in some cases cannot be reversed, even with a return to lower temperatures or CO2 levels."

Humans are emitting about 10 billion tons of CO2 annually, changing the planet much more rapidly than at any time in the last 66 million years, according to a new study. “The anthropogenic release outpaces carbon release during the most extreme global warming event of the past 66 million years, by at least an order of magnitude,” writes Peter Stassen, an Earth and environmental scientist at KU Leuven, in Belgium." “If you look over the entire Cenozoic, the last 66 million years, the only event that we know of at the moment, that has a massive carbon release, and happens over a relatively short period of time, is the PETM,” says Zeebe. “We actually have to go back to relatively old periods, because in the more recent past, we don’t see anything comparable to what humans are currently doing.”

“The scary conclusion is that the East Siberian Arctic Shelf (ESAS) alone holds up to 1700 Gt of methane in the form of methane hydrates and free gas in shallow water, of which 50 Gt is ready for release at any time. The warning signs keep getting stronger,” For comparison purposes, there is currently 5 Gt of methane in the atmosphere. An abrupt release of 50 Gt would be very, very, bad! This is the nightmare scenario that keep scientists up at night.

This is not a "national" crisis. This is a threat to all humanity.

This is not a "national" crisis. This is a threat to all humanity.

Atmospheric CO2 is now reaching levels comparable to those seen during the Middle Miocene. A period of time when the world was both much warmer than today and sea levels were far, far higher. Each year that greenhouse gas emissions continue, more heat, more sea level rise, and more future dangerous climate change is locked in. (Image source: The Keeling Curve.)

“I have talked to scientists all over the world. And what they are telling me — if we don’t get our act together — this planet could be 5-10 degrees warmer by the end of this Century! Cataclysmic problems for this planet! This is a national crisis!” — Bernie Sanders, Michigan Democratic Debate, March 6th.

Sorry, Senator Sanders. It's much, much worse than that.

 2 degrees C warming by 2100, even if we were to make the monumental strides necessary to achieve that limit, is by itself pretty terrible. Though nowhere near as catastrophic as the 3, 4, 5 or 6 C levels of heating that are entirely possible if the world keeps going all out to extract and burn coal, oil and gas, it’s a rate of temperature increase not seen in 55 million years and a level of warming not seen in 2-3 million years. It locks in severe heatwaves the likes of which we’ve never seen before, terrible wildfires, extraordinary rainfall and droughts, monster storms, city-wrecking sea level rise, habitat loss, ocean health decline, glacial melt on a scale that changes the very complexion of the Earth, sea ice winnowing away to a shadow of its former coverage, amplifying Earth System feedbacks, and a whole host of other problems. It also means that the Earth continues to heat up for hundreds of years more unless greenhouse gasses are somehow drawn down — resulting in a long term warming in the range of 4 C so long as climate sensitivity is about what we’ve come to expect from our study of paleoclimate.

Source: http://robertscribbler.com/2016/03/07/climate-change-why-2016-may-be-the-most-important-election-in-us-history/

Climate Change: The state of the Science

. 

Published on Nov 19, 2013

Produced by the International Geosphere-Biosphere Programme and Globaia and funded by the UN Foundation.

The data visualization summarises and visualizes several of the most significant statements in the Intergovernmental Panel on Climate Change's (IPCC) recent Fifth Assessment Report, (Working Group I summary for policymakers, the Physical Science Basis). In 2014, IPCC will publish summaries concerning societal impacts, mitigation and adaptation.

The statements and facts presented are derived from the IPCC summary for policymakers.

Our planet is vast. It is difficult to comprehend the scale. It is difficult too to comprehend the scale of humanity and the vast changes we've wrought in a lifetime. Population, production and consumption have grown exponentially. Roads, railways, airlines, shipping routes. The digital revolution. We've created a globally interconnected society. Evidence is mounting we've entered the Anthropocene.

Humanity is altering Earth's life support system. Carbon dioxide emissions are accelerating. Greenhouse gas levels are unprecedented in human history. The climate system is changing rapidly. The Intergovernmental Panel on Climate Change assesses the risks and options for societies. Its latest report states it is extremely likely humans are the dominant cause of warming in the past 60 years. Without deep emissions cuts, it is likely Earth will cross the target of two degree Celsius above pre-industrial levels. The target set by international policy. This could happen as early as 2050. If emissions keep rising at current rates, a four-degree rise by 2100 is as likely as not. This marks a vast transformation of our planet.

It is very likely heatwaves will occur more often and last longer. The Arctic will warm faster than the global average. It is likely sea ice will all but vanish in summer within decades if high emissions continue. It is very likely sea-level rise will accelerate. Cities and coastal areas are vulnerable. In general, wet regions are set to get wetter, dry regions drier. Monsoons are likely to become longer, their footprint likely to grow and downpours likely to intensify. The acidity of the ocean has increased 26% since the start of the industrial revolution. The full consequences of all these changes on the Earth system are unknown.

Humanity's carbon footprint is huge. Societies will need to adapt to climate change. The scale of change depends on decisions made now. Can we remain below two degrees? It is possible. But it is up to societies now to decide the future we want. For a likely chance of achieving the two-degree target, societies can emit another 250 billion tonnes of carbon. We burn about 10 billion tonnes of carbon a year. At current rates we will use this budget in about 25 years.

Download the IPCC Working Group I summary for policymakers (The Physical Science Basis) here: www.climatechange2013.org

Produced and directed by
Owen Gaffney and Félix Pharand-Deschênes

Animation
Félix Pharand-Deschênes
Globaïa

Script
Owen Gaffney
International Geosphere-Biosphere Programme

Narration
Sarah Sherborne

Data
GEOS-5 atmospheric model
NASA/Goddard Space Flight Center Scientific Visualization Studio
Suomi NPP VIIRS Nighttime Lights 2012
Earth Observation Group, NOAA National Geophysical Data Center
Landscan 2011tm High Resolution global Population Data Set
UT-Battelle, LLC, Oak Ridge National Laboratory
Blue Marble: Next Generation, Reto Stöckli
NASA Earth Observatory, NASA Goddard Space Flight Center
Annual temperature anomaly compared to 1860-1899 period
GFDL-CM3 (historical and RCP8.5 experiments) 1860-2100
Coupled Model Intercomparison Project Phase 5 (CMIP5)
September sea ice concentration
GFDL-CM3 (historical and RCP8.5 experiments) 1860-2100
Coupled Model Intercomparison Project Phase 5 (CMIP5)
Sea level rise flooded areas
Centers for the Remote Sensing of Ice Sheets (CReSIS)
Cyclones tracks
International Best Track Archive for Climate Stewardship (IBTrACS)
Ocean acidification
Max Planck Institute Earth System Model, RCP 8.5

Music
Earlyguard
Continuo VII • Microcosmos • Mind over Matter
earlyguard.bandcamp.com

Commissioned by
International Geosphere-Biosphere Programme
For the launch of the Intergovernmental Panel on Climate Change Working Group I summary for policymakers (Fifth Assessment Report)

Funded by
United Nations Foundation

SPECIAL THANKS TO
Anne-Marie Doucet, Louve & Isis, Myles Allen, Catherine Boire, Wendy Broadgate, David Huard, Tatiana Ilyina, Kalee Kreider, Naomi Lubick, Jochem Marotzke, Johannes Mengel, Tim Nuthall, Sybil Seitzinger, Sturle Hauge Simonsen, Karen Smyth, Simon Torok, Denise Young

This is a product for the WELCOME TO THE ANTHROPOCENE website
anthropocene.info

igbp.net
globaia.org
unfoundation.org

Miami-Dade, Broward and Palm Beach may be underwater in 20-30 years.

Miami-Dade, Broward and Palm Beach counties are underwater in a couple of decades, according to the chairman of the University of Miami’s geological-sciences department

It is time to consider a re-settlement of the millions that live there. 

During high tides that have been worsened by sea-level rise, Miami has seen flooding in its Upper Eastside and Brickell neighborhoods. Hal Wanless, the chairman of the University of Miami’s geological-sciences department, has spent nearly half a century studying South Florida. From this, he’s concluded that the region may have less than half a century more to go. The Intergovernmental Panel on Climate Change predicts sea levels could rise by more than three feet by the end of this century. The United States Army Corps of Engineers projects that they could rise by as much as five feet, and the National Oceanic and Atmospheric Administration predicts up to six and a half feet. According to Wanless, all these projections are all too low.

“We’re looking at the possibility of a ten-to-thirty-foot range by the end of the century,” he told me.

Florida Mayors Tell GOP Climate-Deniers They’ve Had Enough.

Fifteen mayors from cities in Miami-Dade, Broward and Palm Beach counties wrote a letter asking them to meet with local leaders to “discuss the risks facing Florida communities due to climate change and help us chart a path forward to protect our state and the entire United States.”

“As mayors representing municipalities across Florida, we call on you to acknowledge the reality and urgency of climate change and to address the upcoming crisis it presents our communities,” both letters begin. “Our cities and towns are already coping with the impacts of climate change today. We will need leadership and concrete solutions from our next president.”

Got a plan?

NASA and the NOAA agree: 2015 was a record-breaking Hottest year on record.

The experts all agree: 2015 was a record-breaker. 

Last year was the earth's hottest in 136 years of record-keeping, NASA and the National Oceanic and Atmospheric Administration (NOAA) announced Wednesday. The agencies agreed that 2015 was a record-breaker. NOAA found 2015 was 1.62 degrees Fahrenheit warmer than the 20th century average. Since the beginning of modern record keeping, Earth's temperature has risen about 1.8 degrees Fahrenheit, according to NASA, which attributed the change to "increased carbon dioxide and other human-made emissions into the atmosphere."

The average global temperature of 58.24 degrees F. That was already 1.24 degrees above the 20th century average.

"Globally averaged temperatures in 2015 shattered the previous mark set in 2014 by 0.23 degrees Fahrenheit (0.13 Celsius)," NASA reported. "Only once before, in 1998, has the new record been greater than the old record by this much." 2014, the previous hottest year, had an average global temperature of 58.24 degrees Fahrenheit. That was already 1.24 degrees above the 20th century average.

The heat in 2015 can be attributed to both global warming caused by humans and the winter's powerful El Niño event, the World Meteorological Organization said in November. It noted record-high levels of greenhouse gases in the Northern hemisphere last year. 

Fourteen of the last 16 years have been the hottest ever recorded.

Wednesday's announcement is backed up by the Berkeley Earth study released last week, which called 2015 "unambiguously the hottest year on record." "This new high temperature record confirms our previous interpretation that the pause was temporary and that global warming has not slowed," Richard Muller, scientific director of Berkeley Earth, said. (The "pause" was the dozen-plus years before 2014 when global temperatures basically held steady.) The decades-long rise due to greenhouse gas emission is now clearly continuing," added Robert Rohde, the lead scientist on the Berkeley Earth study. 

Democratic presidential candidate Sen. Bernie Sanders (I-Vt.) used the news to urge movement away from fossil fuels. "The debate is over," Sen. Bernie Sanders said. "Fourteen of the last 16 years have been the hottest ever recorded. Climate change is real and is caused by human activity. This planet and its people are in trouble. Unless we get our act together, we will see in years to come more droughts, more floods and more extreme weather disturbances."

While 2015 was a record-breaking year for the planet, it was only the second-hottest year on record for the U.S., which NOAA reported earlier this month saw an average 54.4 degrees F last year. That was 2.4 degrees above the country's 20th century average, but 0.9 degrees under the record 55.3 degree average for 2012.  NASA found that 2015 was 1.8 degrees Fahrenheit warmer than the late 19th century.

“Climate change is the challenge of our generation, and NASA’s vital work on this important issue affects every person on Earth,” NASA Administrator Charles Bolden said in a statement. “Today’s announcement not only underscores how critical NASA’s Earth observation program is, it is a key data point that should make policy makers stand up and take notice - now is the time to act on climate.”

2015 was the hottest year on record.

Experts have been estimating for months that last year would prove to be the world's hottest in over a century. After a NASA report found that this past October was the first month to surpass the 20th century's average temperature by more than 1 degree Celsius, Gavin Schmidt, director of the agency's Goddard Institute for Space Studies, tweeted there was now a 99.9 percent chance that 2015 would be crowned the hottest year on record.

The severe heat was palpable around the planet.

 Europe's Heat Wave.

Heat Records Shattered in Germany, France, The Netherlands in June/July 2015 History's deadliest heat wave -- centered in France in 2003 -- killed 70,000 people across Europe. A dangerous heat wave scorching Europe shattered records and forced people to seek refuge. The heat broke records across Europe in June and July 2015, when triple-digit temperatures settled on Spain, Portugal, France, the United Kingdom, Germany and Poland.

The heat wave in Euorpe in June and July 2015 smashed all-time records.

Madrid (central Madrid) set a new July record high on July 6, topping out at 39.9 degrees Celsius -- 103.8 degrees Fahrenheit, exceeding the previous July record from July 24, 1995 (39.5C). They also set a June record high June 29, reaching 39.7 degrees Celsius -- 103.5 degrees Fahrenheit. Germany's all-time heat record was toppled July 5 in Kitzingen, topping out at 40.3 degrees Celsius (104.5 degrees Fahrenheit). This eclipsed the previous German all-time high of 40.2C (104.4F) from August 2003 and July 1983. German cities set their all-time heat records on the July 4-5 weekend, including Berlin (Dahlem) reaching 37.9C (100.2F) Saturday and Frankfurt soaring to 39C (102.2F) Sunday.

Triple-digit temperatures baked Spain and Portugal before moving on to France, the United Kingdom, Germany, Poland and other areas of Europe. The temperature hit 100 degrees Fahrenheit in Paris in July. And then it kept rising.The official high was 103.5 degrees, just short of the hottest day ever recorded in the French capital. Electricity fluctuations caused by the excessive temperatures briefly blacked out power for 830,000 households on Tuesday night. Near France’s Atlantic coast in the southwestern part of the country, the temperatures rose as high as 108 degrees. Such a high temperature—more typical of California’s Death Valley at this time of year.

Madrid set a new record for its June heat on Monday when temperatures reached 103.5 degrees Fahrenheit, and southern Spain's Cordoba experienced 110.7 degrees on Sunday. A heat of 98.1 degrees at London's Heathrow Airport on Wednesday set a new record for July heat in all of the U.K., while the 103.5 degrees recorded in Paris that same day was the hottest reading in the city since 1873.

Three French locations chalked up all-time record highs, topping their highest 

temperatures from either the 2003 or 2006 heat waves:

- Boulogne-sur-Mer (35.4 Celsius / 95.7 Fahrenheit) beat their previous record from 

Aug. 11, 2003 (34.8C). 

- Dieppe (38.3C / 100.9F) beat their previous record from July 19, 2006 (37C).

- Melun (39.4C / 102.9F) beat their previous record from Aug. 12, 2003 (38.9C).

It wasn't just the high temperatures, lows generally did not drop below 68 degrees (20C) on Saturday morning and for many cities in France they had never recorded such hot nights in July. Lons-le-Saunier in eastern France saw a low of 80 degrees (28C).

Maastricht, in the far southeast of The Netherlands, rose to 38.2 degrees Celsius (100.8F), 

a new national July heat record, topping Westdorpe's 37.1C reading in 2006.

Heat records were broken in Spain.

 Madrid's Adolfo Suarez Madrid-Barajas Airport pushed up to 40 degrees Celsius (104 F), a first for June in records dating to 1945. Four other locations in Spain with records dating to at least the 1950s tied or set new June heat records. Cordoba, Spain, reached a sizzling 43.7 degrees Celsius (110.7F) and topped that July 6 with a high of 45 degrees Celsius (113F).

Research suggests such extreme heat waves, including the one in India that killed more than 1,400 people last month, are largely the result of human-caused climate change. A study published last year in the journal Nature Climate Change found that Europe is now 10 times more likely to see another heat wave as intense as that of 2003 than it was one decade ago.

Temperatures as hot as 36 degrees Celsius (about 97F) were reported in western Poland while Plzen-Mikulka, in the western Czech Republic topped out at 37.8 degrees C Sunday.Even parts of southern Sweden pushed the 32 degrees Celsius (89.6F).The temperature at London's Heathrow Airport skyrocketed to 36.7 degrees Celsius -- 98.1 degrees Fahrenheit -- a July heat record not only there but for anywhere in the U.K., according to the U.K. Met Office. The previous U.K. July heat record was set almost nine years ago -- 36.5 degrees C in Wisley on July 19, 2006. It was also the hottest day in Wimbledon history, topping the previous record of 34.6 degrees C on June 26, 1976.

India and Pakistan: Record heat and floods kills thousands, displace millions.
India's sweltering temperatures have caused 2,500 deaths so far. The temperatures were so hot they melted roads, reaching 45°C (113°F) in New Delhi.

120-degree days in India melted New Delhi's asphalt and killed around 2,500 people.

 In May, 120-degree days in India melted New Delhi's asphalt and killed around 2,500 people, making it the fifth-deadliest heat wave on record. The next month, temperatures as high as 113 degrees killed at least 1,200 people in Pakistan and sent more than 65,000 heatstroke patients to hospitals.

A boy whose house was destroyed by the cyclone watches an approaching storm.

A boy whose house was destroyed by the cyclone watches an approaching storm, some 50 kilometres southwest of the township of Kunyangon. Further storms would complicate relief efforts and leave children increasingly vulnerable to disease. In May 2008 in Myanmar, an estimated 1.5 million people are struggling to survive under increasingly desperate conditions in the wake of Cyclone Nargis, which hit the southwestern coast on 3 May, killed some 100,000 people, and displaced 1 million across five states. Up to 5,000 square kilometres of the densely populated Irrawaddy Delta, which bore the brunt of the storm, remain underwater. 

In Pakistan, over 5.4 million people had been affected by monsoon rains and flooding, this number was expected to rise. In Sindh Province, 824,000 people have been displaced and at least 248 killed. Many government schools have been turned into temporary shelters, and countless water sources have been contaminated. More than 1.8 million people are living in makeshift camps without proper sanitation or access to safe drinking water. Over 70 per cent of standing crops and nearly 14,000 livestock have been destroyed in affected areas, where 80 per cent of the population relies on agriculture for food and income. Affected communities are also threatened by measles, hepatitis and other communicable diseases. The crisis comes one year after the country's 2010 monsoon-related flooding disaster, which covered up to one fifth of the country in flood water and affected more than 18 million people, half of them children. Many families are still recovering from the earlier emergency, which aggravated levels of chronic malnutrition and adversely affected sanitation access and other child protection issues. UNICEF is working with Government authorities and United Nations agencies and partners to provide relief. Thus far, UNICEF-supported programmes have immunized over 153,000 children and 14,000 women; provided nutritional screenings and treatments benefiting over 2,000 children; provided daily safe drinking water to 106,700 people; and constructed 400 latrines benefiting 35,000 people. Still, additional nutrition support and safe water and sanitation services are urgently needed. A joint United Nations Rapid Response Plan seeks US$356.7 million to address the needs of affected populations over the next six months.

Africa: Drought affects food crops as millions go hungry.

Africa: Drought affects food crops as millions go hungry.

A girl carries her baby sibling through a haze of dust in Sidi Village, in Kanem Region. She is taking him to be screened for malnutrition at a mobile outpatient centre for children, operated by one nurse and four nutrition workers. The programme is new to the area. Several months ago, most children suffering from severe malnutrition had to be transported to health centres in the town of Mundo, 12 kilometres away, or in the city of Mao, some 35 kilometres away. In April 2010 in Chad, droughts have devastated local agriculture, causing chronic food shortages and leaving 2 million people in urgent need of food aid. Due to poor rainfall and low agricultural yields, malnutrition rates have hovered above emergency thresholds for a decade. But the 2009 harvest was especially poor, with the production of staple crops declining by 20 percent to 30 percent. Food stocks have since dwindled, and around 30 percent of cattle in the region have died from lack of vegetation. 

Philippines: Massive flooding affects millions.

A boy carries supplies through waist-high floodwater in Pasig City in Manila, the capital. On Sept. 30, 2009, in the Philippines, over half a million people are displaced by flooding caused by Tropical Storm Ketsana, which struck on Sept. 26. The storm dumped over a month's worth of rain on the island of Luzon in only 12 hours. The flooding has affected some 1.8 million people, and the death toll has climbed to 246.

Alex is the first Atlantic hurricane to form in January since 1938.

For the first time on record in January, the National Hurricane Center issued advisories for active tropical cyclones. Alex became the first named tropical weather system to form in the Atlantic during January since 1978. It was classified as a subtropical storm, one that exhibits a combination of tropical and non-tropical characteristics. Alex became the first named Atlantic storm almost six months ahead of average, which is on July 9. In 2015, the first named storm, Ana, — which was also classified as subtropical — formed on May 7. Historically, only 0.5 percent of tropical storm activity has occurred prior to June 1.

“Alex is only the fourth known named storm to form in this month in the historical record that begins in 1851,” the National Hurricane Center wrote Wednesday. The National Hurricane Center seemed stunned by Alex’s strength in its 10 a.m. discussion, writing: “Remarkably, Alex has undergone the transformation into a hurricane. A distinct eye is present, embedded within a fairly symmetric mass of deep convection.” 

Alex has steadily strengthened over the past day and is making history as an extraordinarily rare January hurricane. The National Hurricane Center says Alex is the first Atlantic hurricane to form in January since 1938.  The storm has peak winds of 85 mph, just about 5 mph shy of the 1938 January hurricane, the strongest on record for the month.

Positioned 490 miles south of the Azores, Alex is making a beeline toward the group of islands that sit about 900 miles west of Portugal. The Azores government has issued hurricane warnings for the most of the islands. Only 10 hurricanes on record have tracked within 200 miles of the Azores, all in August or September. “Alex is in a rare spot for September, much less January,” tweeted Eric Blake, a forecaster at the National Hurricane Center. “It is only the 2nd hurricane on record to form north of 30N (latitude) east of 30W (longitude).”

Alex has strengthened over waters that are usually not warm enough to support hurricane activity. However, the contrast between the surface waters and unusually cold air at high altitudes has created a volatile corridor of air, fostering the storm’s development. “The resulting instability is likely the main factor contributing to the tropical transition and intensification of Alex,” the National Hurricane Center wrote in its 10 a.m. discussion.

While the waters in which Alex has developed are, by themselves, not characteristically warm enough for hurricane formation, they are warmer than normal, helping the storm acquire tropical characteristics, according to Weather Underground meteorologist Jeff Masters. “Between January 8 and 12, pre-Alex tracked generally eastwards over ocean waters that were 22 – 25°C (72 – 77°F); these temperatures were near-record warm for this time of year (about 2 – 4°F above average),” Masters wrote. “These temperatures were just high enough so that Alex was able to gradually gain a warm core.”

Masters added that global warming must be considered as a player in the evolution of Alex. “It is unlikely that Alex would have formed if these waters had been close to normal temperatures for this time of year,” he wrote. “The unusually warm waters for Alex were due, in part, to the high levels of global warming that brought Earth its warmest year on record in 2015. Global warming made Alex’s formation much more likely to occur…”

While Alex spun up in the Atlantic, another highly unusual tropical weather system for the time of year was setting milestones in the Pacific. A storm named Pali reached hurricane intensity in the central Pacific Ocean earlier this week, becoming the earliest hurricane to form in that region on record. Located just 4 degrees in latitude north of the equator, Pali also became the third strongest storm to occur so far south on record in the northwest Pacific basin and the strongest storm to occur so close to the equator in the western hemisphere. Pali’s strength and early formation were also supported by much-warmer-than-normal ocean waters in the Pacific, resulting from both this year’s strong El Nino event and ongoing climate warming.

Looking back on a year of unusual weather

Strange Weather Indeed!

Extreme tornadoes in the United States over Christmas, abnormal snowfalls in Mexico, and heavy flooding in South America and the United Kingdom. Perhaps the strangest weather took place in the Northeast, where along the Eastern Seaboard summer-like temperatures made for a green Christmas. It was the warmest Christmas Eve in the history of New York City, where residents and tourists alike strolled the streets in shorts and T-shirts as temperatures hit 72 degrees. It reached 71 degrees in both Philadelphia and Washington, D.C., while normally icy Boston saw the mercury hit 68 degrees. As unseasonably warm temperatures blanketed the Northeast, Southern Californians prepared for snow and ice, and deadly tornadoes swept through the South, claiming at least 20 lives, making for an atypical Christmas Eve in many parts of the United States. Twisters that dotted the landscape from Michigan to Arkansas, along with torrential rains and strong winds. Roads were flooded in Georgia, while other states like Alabama experienced mudslides. Mississippi was hit particularly hard by tornadoes. The death toll in Mississippi, Tennessee, Arkansas and other Southern states had reached 20. Many others were injured, and dozens of homes were damaged or destroyed. Tornado weather is typical in the spring, but can happen anytime cold air meets hot air.

The above-average temperatures seen early this winter were attributed to El Niño, a heating of surface waters in the Pacific Ocean associated with warmer and drier weather. The El Niño currently wreaking havoc around the world is forecast to only worsen in 2016 — and NASA experts fear it could get as bad as the most destructive El Niño ever. A new satellite image of the weather system "bears a striking resemblance to one from December 1997" — the worst El Niño on record — which was blamed for extreme weather, including record rainfall in California and Peru, heat waves across Australia, and fires in Indonesia. The severe conditions resulted in an estimated 23,000 deaths in 1997 and 1998.

This year's El Niño has already caused wild conditions for much of the United States.: It contributed to the reasons why many Americans experienced a balmy Christmas Eve, with temperature peaking in the 70s in places along the East Coast, and is responsible for deadly storms and near-record flooding in the South and Midwest. It also has been tied to the worst floods in five decades in South America.

But a Dec. 27 satellite image from NASA's Jet Propulsion Laboratory, which measures sea surface heights, implies the worst of the droughts and flooding are still to come — a forecast that is troubling to humanitarian relief agencies. In Ethiopia, for example, the government estimates 10.2 million people will need humanitarian assistance next year due to a drought exacerbated by El Niño, Oxfam said. In Malawi, 2.8 million people are estimated to experience food shortages before March.

In the U.S., the biggest El Niño impacts are expected in early 2016, NASA said. The National Oceanic and Atmospheric Administration forecasts "several months of relatively cool and wet conditions across the southern United States, and relatively warm and dry conditions over the northern United States," NASA said.  tornadoes and storms killed more than 20 people in the US states of New Mexico, Texas, Oklahoma, Missouri and Illinois, and flattened hundreds of buildings and houses.

Meanwhile, the intense floods in South America are considered the worst in the past 10 years, forcing more than 170,000 people to evacuate in Paraguay, Argentina, Brazil and Uruguay. “The abnormal flooding is consistent with the prediction made by the World Meteorological Organization (WMO) last November. We cannot ignore science.” Last month, WMO warned that the majority of international climate outlook models indicated that the 2015-16 El Niño weather phenomenon was set to strengthen before the end of the year, causing more flooding and more droughts, setting it among the three strongest since 1950.

The phenomenon, characterized by a warming of the Pacific Ocean, is also triggering a rise in drought in different parts of the Americas, sparking the worst droughts in decades in Central America and Haiti, and that they will continue into 2016.

In Mexico, snowfall over the weekend blanketed 32 towns in the state of Chihuahua, with some places hit by accumulations of 30 centimetres and temperatures of -18 degrees Celsius. December has seen communities in Cumbria, Lancashire, Greater Manchester and Yorkshire in the UK swamped by rising waters with damages that could exceed £1.5 billion. “The repetitive floods in the UK and unusual snowstorms in Mexico are alerting the world about how difficult it is to predict global warming impacts and climate change,” Ms. Wahlström said.

Matt Sitkowski, a coordinating weather producer at The Weather Channel, told NBC News that El Niño could result in a "wetter and stormier California" for the next two to three months — which could be a boon for the drought-stricken state. "The fear is some of these storms come and you get too much at once, which could lead to flooding concerns," he added. "It doesn't take much in parts of California."

"The El Niño weather system could leave tens of millions of people facing hunger, water shortages and disease next year if early action isn't taken to prepare vulnerable people from its effects," aid agency Oxfam International warned in a press release.

Meanwhile, holiday travelers in Southern California prepared for a cold system Thursday that was expected to bring rain, cold and snow in mountainous areas. Portions of Interstate 5, the main highway on the West Coast, were to become blanketed with snow and ice. Forecasters also were expecting wind gusts of up to 45 mph.