Other Effects of Climate Change

This page gives links to science articles that discuss the effects of changes in temperatures on the earth.

"The study did not seek to estimate how much the planet will warm, or how rapidly sea levels will rise," noted Peter Clark, an Oregon State University paleoclimatologist and author on the PNAS article. "Instead, we were trying to pin down the 'sea-level commitment' of global warming on a multi-millennial time scale. In other words, how much would sea levels rise over long periods of time for each degree the planet warms and holds that warmth?"

One often ignored consequence of global climate change is that the Northern Hemisphere is becoming warmer than the Southern Hemisphere, which could significantly alter tropical precipitation patterns, according to a new study by climatologists from the University of California, Berkeley, and the University of Washington, Seattle.

Using data from 73 sites around the world, scientists have been able to reconstruct Earth's temperature history back to the end of the last Ice Age, revealing that the planet today is warmer than it has been during 70 to 80 percent of the time over the last 11,300 years.

In 2012, the contiguous United States (CONUS) average annual temperature of 55.3°F was 3.2°F above the 20^th century average, and was the warmest year in the 1895-2012 period of record for the nation. The 2012 annual temperature was 1.0°F warmer than the previous record warm year of 1998. Since 1895, the CONUS has observed a long-term temperature increase of about 0.13°F per decade. Precipitation averaged across the CONUS in 2012 was 26.57 inches, which is 2.57 inches below the 20th century average. Precipitation totals in 2012 ranked as the 15^th driest year on record. Over the 118-year period of record, precipitation across the CONUS has increased at a rate of about 0.16 inch per decade.

The globally-averaged temperature for 2012 marked the 10^th warmest year since record keeping began in 1880. It also marked the 36^th consecutive year with a global temperature above the 20^th century average. The last below-average annual temperature was 1976. Including 2012, all 12 years to date in the 21^st century (2001-2012) rank among the 14 warmest in the 133-year period of record. Only one year during the 20^st century -- 1998 -- was warmer than 2012.

In the most comprehensive review of changes to extreme rainfall ever undertaken, researchers evaluated the association between extreme rainfall and atmospheric temperatures at more than 8000 weather gauging stations around the world.

"The last decade brought unprecedented heat waves; for instance in the US in 2012, in Russia in 2010, in Australia in 2009, and in Europe in 2003," lead-author Dim Coumou says. "Heat extremes are causing many deaths, major forest fires, and harvest losses -- societies and ecosystems are not adapted to ever new record-breaking temperatures." The new study relies on 131 years of monthly temperature data for more than 12,000 grid points around the world, provided by NASA. Comprehensive analysis reveals the increase in records.

According to NOAA scientists, 2012 marked the warmest year on record for the contiguous United States with the year consisting of a record warm spring, second warmest summer, fourth warmest winter and a warmer-than-average autumn. The average temperature for 2012 was 55.3°F, 3.2°F above the 20th century average, and 1.0°F above 1998, the previous warmest year.

CSIRO scientists Wenju Cai, Tim Cowan and Marcus Thatcher explored why autumn rainfall has been in decline across south-eastern Australia since the 1970s, a period that included the devastating Millennium drought from 1997-2009.

Research undertaken by the University of Southampton and its associates in Venice has revealed that the sea surface temperature (SST) in coastal regions is rising as much as ten times faster than the global average of 0.13 degrees per decade.
Researchers believe that this is partly as a result of a process known as the 'urban heat island effect'; where regions experiencing rapid industrial and urban expansion produce vast amounts of heat, making the area warmer than its surroundings.

Satellite measurement of sea surface temperatures has yielded clear evidence of major changes taking place in the waters of Australia's Great Barrier Reef over the past 25 years, marine scientists have found.

During the first six months of 2012, sea surface temperatures in the Northeast Shelf Large Marine Ecosystem were the highest ever recorded, according to the latest Ecosystem Advisory issued by NOAA's Northeast Fisheries Science Center (NEFSC). Above-average temperatures were found in all parts of the ecosystem, from the ocean bottom to the sea surface and across the region, and the above average temperatures extended beyond the shelf break front to the Gulf Stream.

Gardeners and landscapers may want to rethink their fall tree plantings. Warming temperatures have already made the U.S. Department of Agriculture's new cold-weather planting guidelines obsolete, according to Dr. Nir Krakauer, assistant professor of civil engineering in The City College of New York's Grove School of Engineering.

Hurricanes in the Atlantic are increasing because of natural weather patterns rather than global warming, a study has concluded. [posted by The Times (online) on June 7, 2007].

The IPCC’s fourth and final assessment of the climate change problem—known as the Synthesis Report—combines all of these reports and adds that “warming could lead to some impacts that are abrupt or irreversible, depending upon the rate and magnitude of the climate change.”

Warmer temperatures are only part of the problem, explained geographer Thomas Painter of the University of Utah, Salt Lake City, who presented his own research on snowpack in the West at the meeting. Also contributing is carbon black, known more commonly as soot, which continually rains down on the glaciers but tends to concentrate on the surface of the ice. By the calculations of his research team, Painter said, soot increases heat absorption from the sun's rays by 43%. That provides "yet another reason" to limit carbon black from industrial emissions, says climatologist Claire Parkinson of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Duffy asked Marohasy: “Is the Earth still warming?” She replied: “No, actually, there has been cooling, if you take 1998 as your point of reference. If you take 2002 as your point of reference, then temperatures have plateaued. This is certainly not what you’d expect if carbon dioxide is driving temperature because carbon dioxide levels have been increasing but temperatures have actually been coming down over the last 10 years.”

A group of 3,146 earth scientists surveyed around the world overwhelmingly agree that in the past 200-plus years, mean global temperatures have been rising, and that human activity is a significant contributing factor in changing mean global temperatures.

Scientists from the Complutense University of Madrid (UCM) have selected 262 European observatories which analysed the series of minimum and maximum daily temperatures from 1955 to 1998 to estimate trend variations in extreme temperature events. According to the study, in Europe days of extreme cold are decreasing and days of extreme heat increasing. From 0.5ºC to 1ºC in the average minimum temperature, and from 0.5ºC to 2ºC in the average maximum temperature.

The Arctic and Antarctic regions are warming faster than previously thought, raising world sea levels and making drastic global climate change more likely than ever, international scientists said on Wednesday. [posted by NewsDaily on February 25, 2009]

“There’s always interest in the annual temperature numbers and a given year’s ranking, but the ranking often misses the point,” said James Hansen, GISS director. “There’s substantial year-to-year variability of global temperature caused by the tropical El Nino-La Nina cycle. When we average temperature over five or ten years to minimize that variability, we find global warming is continuing unabated.”

“The vast amount of heat stored in the ocean regulates Earth’s temperature, much as a flywheel regulates the speed of an engine,” said Bill Patzert, an oceanographer and climatologist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The ocean has a long history of capturing and giving up heat generated by both human activities and natural cycles; it is the thermal memory of the climate system.”

The GRL study took two years to complete and is co-authored by Moetasim Ashfaq, a former Stanford postdoctoral fellow now at the Oak Ridge National Laboratory. The study comes on the heels of a recent NASA report, which concluded that the previous decade, January 2000 to December 2009, was the warmest on record.

The contiguous United States had its fourth-warmest summer (June-August) on record, according to the latest NOAA State of the Climate report issued September 8. The report also showed the August average temperature was 75.0 degrees F, which is 2.2 degrees F above the long-term (1901-2000) average. Last month’s average precipitation was 2.41 inches, 0.19 inch below the 1901-2000 average.

The first eight months of 2010 tied the same period in 1998 for the warmest combined land and ocean surface temperature on record worldwide. Meanwhile, the June-August summer was the second warmest on record globally after 1998, and last month was the third warmest August on record. Separately, last month’s global average land surface temperature was the second warmest on record for August, while the global ocean surface temperature tied with 1997 as the sixth warmest for August.

In the 1990s, observations did not show the troposphere, particularly in the tropics, to be warming, even though surface temperatures were rapidly warming. This lack of tropospheric warming was used by some to question both the reality of the surface warming trend and the reliability of climate models as tools. This new paper extensively reviews the relevant scientific analyses — 195 cited papers, model results and atmospheric data sets — and finds that there is no longer evidence for a fundamental discrepancy and that the troposphere is warming.

In the first comprehensive global survey of temperature trends in major lakes, NASA researchers determined Earth’s largest lakes have warmed during the past 25 years in response to climate change.

The analysis found 2010 approximately 1.34 F warmer than the average global surface temperature from 1951 to 1980. To measure climate change, scientists look at long-term trends. The temperature trend, including data from 2010, shows the climate has warmed by approximately 0.36 F per decade since the late 1970s.

In a study published Oct. 25, 2011, in IOP Publishing’s Environmental Research Letters, scientists examined data from 111 weather stations across south-western China and have shown that temperature patterns were consistent with warming, at a statistically significant level, between 1961 and 2008.

Since 1975, five high-elevation lakes in the Adirondacks have had rapid decreases in the duration of ice cover and are now frozen for 7 to 21 fewer days on average, according to a study published April 30 in the journal Climatic Change by a team of researchers at the SUNY College of Environmental Science and Forestry (ESF).

One popular climate record that shows a slower atmospheric warming trend than other studies contains a data calibration problem, and when the problem is corrected the results fall in line with other records and climate models, according to a new University of Washington study.

According to NOAA scientists, the average temperature for the contiguous U.S. during May was 64.3°F, 3.3°F above the long-term average, making it the second warmest May on record. The month's high temperatures also contributed to the warmest spring, warmest year-to-date, and warmest 12-month period the nation has experienced since recordkeeping began in 1895.

By the end of the century, almost all of North America and most of Europe is projected to see a jump in the frequency of wildfires, primarily because of increasing temperature trends. At the same time, fire activity could actually decrease around equatorial regions, particularly among the tropical rainforests, because of increased rainfall.

A groundbreaking new study led by UCLA climate expert Alex Hall shows that climate change will cause temperatures in the Los Angeles region to rise by an average of 4 to 5 degrees Fahrenheit by the middle of this century, tripling the number of extremely hot days in the downtown area and quadrupling the number in the valleys and at high elevations.

The recent heat wave baking much of the country has prompted many people to ask: Is this due to climate change?

"This is always the million-dollar question, but unfortunately, there's no definitive way to answer it," says Steve Vavrus, a senior scientist in the Nelson Institute Center for Climatic Research at the University of Wisconsin-Madison. "We've experienced extreme heat, drought, floods, wildfires and windstorms throughout history, so in a sense this is nothing unusual. We need time to assess whether this year's set of extreme weather events falls outside of normal variations."

Climate change drove coral reefs to a total ecosystem collapse lasting thousands of years, according to a paper published this week in Science. The paper shows how natural climatic shifts stopped reef growth in the eastern Pacific for 2,500 years. The reef shutdown, which began 4,000 years ago, corresponds to a period of dramatic swings in the El Niño-Southern Oscillation (ENSO). "As humans continue to pump greenhouse gases into the atmosphere, the climate is once again on the threshold of a new regime, with dire consequences for reef ecosystems unless we get control of climate change," said coauthor Richard Aronson, a biology professor at Florida Institute of Technology.

An international team that includes scientists from Johannes Gutenberg University Mainz (JGU) has published a reconstruction of the climate in northern Europe over the last 2,000 years based on the information provided by tree-rings. Professor Dr. Jan Esper's group at the Institute of Geography at JGU used tree-ring density measurements from sub-fossil pine trees originating from Finnish Lapland to produce a reconstruction reaching back to 138 BC. In so doing, the researchers have been able for the first time to precisely demonstrate that the long-term trend over the past two millennia has been towards climatic cooling.

Researchers are working to identify exactly how a changing climate will impact specific elements of weather, such as clouds, rainfall, and lightning. A Tel Aviv University researcher has predicted that for every one degree Celsius of warming, there will be approximately a 10 percent increase in lightning activity.

Global warming also affects lakes. Based on the example of Lake Zurich, researchers from the University of Zurich demonstrate that there is insufficient water turnover in the lake during the winter and harmful Burgundy blood algae are increasingly thriving. The warmer temperatures are thus compromising the successful lake clean-ups of recent decades.

The study was led by researchers at the University of Melbourne and used a range of natural indicators including tree rings, corals and ice cores to study Australasian temperatures over the past millennium and compared them to climate model simulations.

The 20 scientists involved in the project concluded that there were fewer fires following the onset of a global cooling trend hundreds of years ago. Conversely, there were more fires after the trend reversed into a period of global warming.

If you live in the Northeast, welcome to the hottest year on record. New data released by the Northeast Regional Climate Center at Cornell University shows the Northeast's seven-month average (January through July) of 49.9 degrees was the warmest such period since 1895, the year such record keeping began. It was the second warmest such period in Pennsylvania and West Virginia, and the warmest first seven months of the year in the rest of the Northeast.

A new statistical analysis by NASA scientists has found that Earth's land areas have become much more likely to experience an extreme summer heat wave than they were in the middle of the 20th century.

According to NOAA scientists, the average temperature for the contiguous U.S. during July was 77.6°F, 3.3°F above the 20th century average, marking the hottest July and the hottest month on record for the nation. The previous warmest July for the nation was July 1936 when the average U.S. temperature was 77.4°F. The warm July temperatures contributed to a record-warm first seven months of the year and the warmest 12-month period the nation has experienced since recordkeeping began in 1895.

Research has revealed that the extremely hot, dry and windy conditions on Black Saturday in the Australian state of Victoria combined with structures in the atmosphere called 'horizontal convective rolls' -- similar to streamers of wind flowing through the air -- which likely affected fire behaviour.

The study, which is reported in the journal Science, offers new insights into a decades-long debate about how the shifts in Earth's orbit relative to the sun have taken Earth into and out of an ice-age climate.

The lack of rainfall has decimated many corn crops, which were damaged as a result of not enough rain during its crucial pollination period. So even though growers planted a record acreage of corn this year in anticipation of a strong year with record yields, the lack of enough rainfall has caused yield forecasts to continue to decline, Roberts said.

A new study led by scientists at the University of York has shown how birds, butterflies, other insects and spiders have colonised nature reserves and areas protected for wildlife, as they move north in response to climate change and other environmental changes.

Climate researchers Alexander Gershunov and Kristen Guirguis detected a trend toward more humid heatwaves that are expressed very strongly in elevated nighttime temperatures, a trend consistent with climate change projections. Moreover, relative to local warming, the mid-summer heatwaves are getting stronger in generally cooler coastal areas. This carries implications for the millions of Californians living near the ocean whose everyday lives are acclimated to moderate temperatures.

Viewed as a potential target in the global effort to reduce climate change, atmospheric black carbon particles absorb significantly less sunlight than scientists predicted, raising new questions about the impact of black carbon on atmospheric warming, an international team of researchers, including climate chemists from Boston College, report August 30 in the latest edition of the journal Science.