Climate is the long-term pattern of weather in a particular area. It is measured by assessing the patterns of variation in temperature, humidity, atmospheric pressure, wind, precipitation, atmospheric particle count and other meteorological variables in a given region over long periods of time. Climate is different from weather, in that weather only describes the short-term conditions of these variables in a given region.

A region's climate is generated by the climate system, which has five components: atmosphere, hydrosphere, cryosphere, lithosphere, and biosphere.

The climate of a location is affected by its latitude, terrain, and altitude, as well as nearby water bodies and their currents. Climates can be classified according to the average and the typical ranges of different variables, most commonly temperature and precipitation. The most commonly used classification scheme was originally developed by Wladimir Koppen. The Thornthwaite system, in use since 1948, incorporates evapotranspiration along with temperature and precipitation information and is used in studying animal species diversity and potential effects of climate changes. The Bergeron and Spatial Synoptic Classification systems focus on the origin of air masses that define the climate of a region.

Paleoclimatology is the study of ancient climates. Since direct observations of climate are not available before the 19th century, paleoclimates are inferred from proxy variables that include non-biotic evidence such as sediments found in lake beds and ice cores, and biotic evidence such as tree rings and coral. Climate models are mathematical models of past, present and future climates. Climate change may occur over long and short timescales from a variety of factors; recent warming is discussed in global warming. Read more ...

June 2, 2017 - The day after ... Trump withdrew the US from the Paris Climate Accord

In the News ...

Climate is warming faster than it has in the last 2,000 years   Science Daily - July 24, 2019
Two new studies show that the 20th century was the Earth's warmest period recorded in 2,000 years of the planet's record.The studies further indicate that global warming was manmade because the warming trend began after the industrial revolution, according to climate scientist Julien Emile-Geay, associate professor of Earth sciences at USC Dornsife College of Letters, Arts and Sciences and a co-author of one of the studies.

South Australia's droughts are getting worse   PhysOrg - June 14, 2019
Despite Adelaide experiencing its wettest day in more than two years this month, a new study by UniSA shows droughts are becoming longer and more severe in South Australia.

America colonization ‘cooled Earth's climate’   BBC - January 31, 2019
Colonization of the Americas at the end of the 15th Century killed so many people, it disturbed Earth's climate. The disruption that followed European settlement led to a huge swathe of abandoned agricultural land being reclaimed by fast-growing trees and other vegetation. This pulled down enough carbon dioxide from the atmosphere to eventually chill the planet. It's a cooling period often referred to in the history books as the "Little Ice Age" - a time when winters in Europe would see the Thames in London regularly freeze over. The Great Dying of the Indigenous Peoples of the Americas led to the abandonment of enough cleared land that the resulting terrestrial carbon uptake had a detectable impact on both atmospheric carbon dioxide and global surface air temperatures.

Monster Waves Are Battering the West Coast. Here's Why.   Live Science - December 19, 2018
Cyclonic winds, rushing down from Alaska had nothing else to batter against, so they smacked into the water across miles of open ocean. The winds pushed and ground and heaved against the waves, making them bigger, more sustained and more powerful. By the time these waves reached the U.S. shoreline, they were massive, prompting the National Weather Service (NWS) to issue high-surf alerts up and down the West Coast beginning Sunday (Dec. 16) and in many cases remaining in effect until midday today (Dec. 18).

'Pause' in global warming was never real, new research proves   PhysOrg - December 18, 2018
Claims of a 'pause' in observed global temperature warming are comprehensively disproved in a pair of new studies published today. An international team of climate researchers reviewed existing data and studies and reanalyzed them. They concluded there has never been a statistically significant 'pause' in global warming. This conclusion holds whether considering the `pause' as a change in the rate of warming in observations or as a mismatch in rate between observations and expectations from climate models.

Rare blitz of tornadoes leaves central Illinois with damage, injuries   CNN - December 2, 2018
"It's a miracle no one was killed in the tragedy of these tornadoes," said Gov. Bruce Rauner.

Climate change could trigger an 'extinction domino effect' that would annihilate all life on Earth, chilling report warns   Daily Mail - November 30, 2018

New automated volcano warning system forecasts imminent eruptions   PhysOrg - November 29, 2018

This Strange Hum Circled the Whole World. But Nobody Heard It. It was a seismic event that originated off the coast of Mayotte on Nov. 11 a tiny island in the waters between Madagascar and Mozambique   Live Science - November 29, 2018

Antarctic Island Exploded 4,000 Years Ago   Live Science - November 29, 2018

Deceptive and Dangerous: A Gallery of An Antarctic Volcano   Live Science - November 29, 2018

Climate change: Last four years are 'world's hottest'   BBC - November 29, 2018

Fossil algae reveal 500 million years of climate change   PhysOrg - November 28, 2018

Fires fueled spread of grasslands on ancient Earth   PhysOrg - November 28, 2018

Wildfires bring climate's dark forces to the stratosphere   PhysOrg - November 27, 2018

Climate change could lead to threefold increase in powerful storms across Europe and North America   PhysOrg - November 27, 2018

Extreme heat increasing in both summer and winter   PhysOrg - November 27, 2018

Ocean circulation in North Atlantic at its weakest   PhysOrg - November 27, 2018

How the Atlantic Ocean became part of the global circulation at a climatic tipping point   PhysOrg - November 27, 2018

Strong chance of a new El Nino forming by early 2019   BBC - November 27, 2018

Death will be one of the highest economic costs of climate change   Technology review - November 27, 2018

Climate change: CO2 emissions rising for first time in four years   BBC - November 27, 2018

Climate change will shrink US economy and kill thousands, government report warns   CNN - November 26, 2018

Bernie Sanders on climate change report: 'The future of the planet is at stake'   CNN - November 27, 2018

Get Used to Nor'easters - Arctic Warming May Mean More Severe Winters in the Northeast   Live Science - March 16, 2018
As average temperatures rise across the planet, the frozen Arctic is heating up faster than anywhere else. With that warmth comes a surprising twist: Unusually warm Arctic winter temperatures are linked to bitter cold and snow in other parts of the Northern Hemisphere, such as the northeastern U.S., parts of northern Europe and northern Asia, according to an analysis of 66 years worth of climate data. And the relationship between Arctic warmth and severe winter weather was strongest in in the northeastern U.S. - in fact, a temperature spike in the Arctic meant that the U.S. Northeast was two to four times more likely than usual to experience a bout of extreme winter weather, the scientists reported in a new study.

East Coast of the USA is slowly sinking into the sea   Science Daily - September 11, 2017
The East Coast of the United States is threatened by more frequent flooding in the future. According to this study, the states of Virginia, North Carolina, and South Carolina are most at risk. Their coastal regions are being immersed by up to three millimeters per year -- among other things, due to human intervention.

Uncontrollable Wildfires Could Double in Canada Due to Climate Change   Seeker - July 12, 2017
Major conflagrations such as those that erupted in recent years in Canada, the United States, Russia, and Portugal could become more frequent and more intense, reaching a point where fire suppression becomes of little help. Climate change could more than double the odds of uncontrollable fires in Canada's vast forests, producing conditions that make it impossible for firefighters to battle those blazes, a new study concludes. Higher temperatures mean drier vegetation and more lightning. And in a combination of scenarios involving computer models of atmospheric circulation and carbon emissions through the end of the century, scientists from Canada’s government and the University of Alberta found that would mean large increases in the number of fires “where existing suppression resources become ineffective.”

  Record rainfall and floods hit Paris   BBC - July 10, 2017
A two-hour storm unleashed 54mm (2.1in) of rain on Sunday night in Paris, the equivalent of 27 days of rainfall. Weather services say 49.2mm fell in one hour, the French capital's heaviest July deluge on record. Flooding closed 20 metro stations and three were still shut as commuters made their way to work on Monday morning. Parts of Switzerland were hit by violent winds and hail storms that also caused flooding at the weekend.

  When corals die off, we die off   CNN - July 10, 2017
Thanks to climate change, the ocean is no longer a friend of Seychelles. But can its reefs offer this embattled nation a lifeline?

  Thousands Flee Wildfires in California; Canada Blazes Grow   US News - July 10, 2017

  Climate Change Could Cut Southern U.S. Incomes by 20%   Fortune - July 10, 2017

Stalagmites from Iranian cave foretell grim future for Middle East climate   PhysOrg - July 10, 2017

The Uninhabitable Earth   New York Magazine - July 10, 2017

Just 100 companies responsible for 71% of global emissions, study says   The Guardian - July 10, 2017

'Extreme and unusual' climate trends continue after record 2016   BBC - March 21, 2017
Check out the map. In the atmosphere, the seas and around the poles, climate change is reaching disturbing new levels across the Earth. That's according to a detailed global analysis from the World Meteorological Organization (WMO).

Climate change: Data shows 2016 likely to be warmest year yet   BBC - January 19, 2017
Temperature data for 2016 shows it is likely to have edged ahead of 2015 as the world's warmest year.

North Pole Forecast To Be 50 Degrees Warmer Than Normal This Week   Huffington Post - December 22, 2016
Temperatures in the Arctic are predicted to soar nearly 50 degrees above normal on Thursday in a pre-Christmas heat wave that will bring the frozen tundra scarily close to the melting point. It's the second year in a row the North Pole - now in perpetual darkness after saying goodbye to the sun in late October - has seen abnormally high temperatures around the Christmas holiday. It's also the second time this year. In November, temperatures in the region skyrocketed 36 degrees above normal.

Over 90% of world breathing bad air: WHO   PhysOrg - September 27, 2016
The problem is most acute in cities, but air in rural areas is worse than many think, WHO experts said. Poorer countries have much dirtier air than the developed world, according to the report, but pollution affects practically all countries in the world and all parts of society.

Methane was not the climate savior once imagined for the middle chapter of Earth history   PhysOrg - September 27, 2016
For at least a billion years of the distant past, planet Earth should have been frozen over but wasn't. Scientists thought they knew why, but a new modeling study from the Alternative Earths team of the NASA Astrobiology Institute has fired the lead actor in that long-accepted scenario.

Ancient global cooling gave rise to modern ecosystems   PhysOrg - September 27, 2016
Around 7 million years ago, landscapes and ecosystems across the world began changing dramatically. Subtropical regions dried out and the Sahara Desert formed in Africa. Rain forests receded and were replaced by the vast savannas and grasslands that persist today in North and South America, Africa and Asia. Up to now, these events have generally been explained by separate tectonic events - the uplift of mountain ranges or the alteration of ocean basins - causing discrete and local changes in climate. But in a new study, a team of researchers has shown that these environmental changes coincided with a previously undocumented period of global cooling, which was likely driven by a sharp reduction in atmospheric carbon dioxide.

Study: Earth's roughly warmest in about 100,000 years   PhysOrg - September 26, 2016
A new study paints a picture of an Earth that is warmer than it has been in about 120,000 years, and is locked into eventually hitting its hottest mark in more than 2 million years.

Oldest pine fossils reveal fiery past   Science Daily - March 10, 2016
The oldest fossils of the familiar pine tree that dominates Northern Hemisphere forests today has been found by researchers. The 140-million-year-old fossils (dating from the Cretaceous 'Age of the Dinosaurs') are exquisitely preserved as charcoal, the result of burning in wildfires. Scientists have found the oldest fossils of the familiar pine tree that dominates Northern Hemisphere forests today. Scientists from the Department of Earth Sciences at Royal Holloway, University of London have found the oldest fossils of the familiar pine tree that dominates Northern Hemisphere forests today. The 140-million-year-old fossils (dating from the Cretaceous 'Age of the Dinosaurs') are exquisitely preserved as charcoal, the result of burning in wildfires. The fossils suggest that pines co-evolved with fire at a time when oxygen levels in the atmosphere were much higher and forests were especially flammable.

Americans Still Don't Know What Climate Change Is, Google Shows   Huffington Post - December 14, 2015
World leaders took a major step forward Saturday when they reached an accord on curbing the climate change crisis facing our planet -- but if Google search data is anything to go by, Americans are barely aware that there was a problem to begin with. A look at Google Trends data on Monday shows that the "top questions" people in the United States typed into the search engine include "Is climate change real?" and "Why is climate change important?" Google's data shows that, in the past week, the United States ranked 56th in terms of interest in the COP21 summit. Togo, Cameroon and Burkina Faso were the top three most interested, according to the search data. Top questions on Climate Change

  Cold Atlantic 'blob' puzzles scientists   CNN - September 30, 2015
At first glance, it stands out like a sore thumb. That blob of blue and purple on the map. One of the only places on the globe that is abnormally cold in a year that will likely shatter records as the warmest globally. It's being called the Atlantic "blob." It's a large area in the North Atlantic that is seeing a pronounced cooling trend. The ocean surface is much cooler than normal and in fact record cold in some locations. Scientists began to notice it developing over the last couple of years, this cooling in the Atlantic is the complete opposite of the warming over in the Pacific. Much of the warming is attributed to El Nino, a natural process where warm water sloshes over the Central Pacific and extends to South America, but scientists are unable to completely explain what has been dubbed the Pacific Blob. This pronounced warming over large areas of the entire Pacific basin has fueled a well above average season for hurricanes and typhoons over the entire Pacific, and could have contributed to everything from the California drought, impacts on the salmon industry, and even tropical sharks seen in waters further north than ever before.

Should we fear the North Atlantic Blob? Climate scientists warn record cold in ocean may be a sign of changes to ocean currents   Daily Mail - September 30, 2015
The planet is on course to experience one of its warmest years on record, but scientists have been left baffled by a massive cold patch in the North Atlantic Ocean. The area, which lies just to the south of Greenland and Iceland, is showing some of the coldest temperatures ever recorded for the region. It comes at a time large parts of the world are experiencing some of the hottest on record, raising fears the recent 'pause' in global warming has come to an end.

Deciphering clues to prehistoric climate changes locked in cave deposits   PhysOrg - May 23, 2015
When the conversation turns to the weather and the climate, most people's thoughts naturally drift upward toward the clouds, but Jessica Oster's sink down into the subterranean world of stalactites and stalagmites. It turns out that the steady dripping of water deep underground can reveal a surprising amount of information about the constantly changing cycles of heat and cold, precipitation and drought in the turbulent atmosphere above. As water seeps down through the ground it picks up minerals, most commonly calcium carbonate. When this mineral-rich water drips into caves, it leaves mineral deposits behind that form layers which grow during wet periods and form dusty skins when the water dries up.

Is There a Climate Crystal Ball?   Live Science - April 2, 2014
When it comes to what society should do about global warming, there is quite a lot to consider. While reducing emissions is the clear end-goal, the speed at which it's done and how much of today's time and money is spent on mitigation or adaptation depends on how much immediate danger climate change presents during our lifetimes, or those of the next generation. It's the near future most people are concerned with - perhaps too concerned when "near future" is a synonym for "my electoral term in office" or "my spell as CEO." The overall effect of manmade greenhouse gases on the climate is modeled in different ways, but only one measure is considered "policy relevant." It's called Transient Climate Response (TCR), defined as the global mean-temperature change on the day that carbon dioxide (CO2)has doubled over pre-industrial levels, given a rate of increase of 1 percent per year. Climate scientists believe that Earth will reach a doubling of CO2 within the lifetime of a child born this year. If TCR is high, society must act very quickly, and the amount spent must be proportional to the immediacy of the danger. If TCR is low, then temperatures won't go up much, in which case there is more time, and people can spend less money now.

Reading ancient climate from plankton shells   PhysOrg - October 25, 2013
Climate changes from millions of years ago are recorded at daily rate in ancient sea shells, new research shows. It's important to understand current climate change in the light of how climate has varied in the geological past. One way to do this, for the last few thousand years, is to analyze ice from the poles. The planet's temperature and atmosphere are recorded by bubbles of ancient air trapped in polar ice cores. The oldest Antarctic ice core records date back to around 800,000 years ago.

Climate change occurring 10 times faster than at any time in past 65 million years   PhysOrg - August 1, 2013
The planet is undergoing one of the largest changes in climate since the dinosaurs went extinct. But what might be even more troubling for humans, plants and animals is the speed of the change. Stanford climate scientists warn that the likely rate of change over the next century will be at least 10 times quicker than any climate shift in the past 65 million years.

Hot and bothered: Climate change amplifies violence, study says   NBC - August 1, 2013
As the planet's climate changes, humans everywhere should brace for a spike in violence, a new study suggests. Civilization as we know it may even be at risk.