Global Warming Facts

Global Warming facts provides information related to the theory that increased atmospheric emissions of greenhouse gases (GHGs), are warming the planet.

Six Greenhouse Gases

  • carbon dioxide (CO2)
  • methane (CH4)
  • nitrous oxide (N2O)
  • hydrofluorocarbons (HFCs)
  • perfluorocarbons (PFCs)
  • sulphur hexafluoride (SF6)

Polar Regions

Climate changes in and around Antarctica have been comparatively less pronounced to date than climate induced changes around the Arctic region, however, a series of recent reports by the Scientific Committee on Antarctic Research (SCAR), suggests that the scenario will soon change.

Their conclusion, "Assuming a doubling of greenhouse gas concentrations over the next century, Antarctica is expected to warm by around 3oC." (or approximately 5.4oF)

Questions related to the reasons for the delayed observable warming patterns across Antarctica persist.

Answering those questions begins by comparing Antarctica and Arctic geography. Basically they mirror image each other. Whereas the north pole is an ice covered ocean surrounding by land, the south pole is an ice covered land mass surrounding by oceans.

In addition to geographical differences between the two polar places, the IPCC 2007 Fourth Assessment explained some of the differences between the climate change effects in the north and south as a lack of data, saying,

A serious problem is the lack of observations against which to assess models, and for developing process knowledge, particularly over Antarctica.

The 2014 Fifth Assessment notes improvement in Antarctica data, and therefore Antarctic climate projections, although researchers also note that comparatively speaking, Arctic data tends to still be a tad bit more reliable than Antarctic data, due in no small part to comparable abundance of Arctic climate related research versus Antarctic climate related research. The Fifth Assessment big picture climate projection for Antarctic says,

In the Southern Hemisphere, the strongest rates of atmospheric warming are occurring in the western Antarctic Peninsula (WAP, between 0.2 and 0.3 °C per decade) and the islands of the Scotia Arc, where there have also been increases in oceanic temperatures and large regional decreases in winter sea ice extent and duration. Warming, although less than WAP, has also occurred in the continental margins near to Bellingshausen Sea, Prydz Bay and the Ross Sea, with areas of cooling in between. Land regions have experienced glacial recession and changes in the ice and permafrost habitats in the coastal margins. The Southern Ocean continues to warm, with increased freshening at the surface due to precipitation leading to increased stratification.

Arctic Sea Ice

The General Circulation Models (GCMs) used to model climate change have consistently suggested that the greatest impact of climate change will be felt in the polar regions. To date, the changing Arctic ecology fails to falsify the results of the scientific models.

Rates of sea ice change slightly from year to year, however over time, statistics show consistent loss. While increasing temperatures in the Arctic region account for some of the ice thinning, the melting is more fully explained by a double causative model that includes increased air temperatures and a changing ocean ecosystem.

Maps provided by the Arctic Climatology Project, a cooperative United States-Russian program, were among the first to illustrate an overall thinning pattern for the polar ice cap. One set of maps, for example, contrasted ice thickness at a 75 meter depth in the 1950s and in the 1980s, discovering ice pack density decreases in the potentially most dense ice packs off the coast of Norway and Russia. They also showed overall density thinning throughout the entire Arctic Ocean.

Why the thinning? Most scientists attribute the thinning to a weakening of the halocline layer of the Arctic Ocean, which basically is the bottom portion of the top layer of the three layers of water constituting the Arctic Ocean. The halocline layer, defined by its strong salinity, traditionally functioned as a road block, stopping the warmer Atlantic Ocean water (the Atlantic layer= 2nd level of Arctic Ocean) from mixing with and melting the top layer, the ice.

Russian Permafrost and Climate Change

A changing climate contines to alter Russian permafrost. Environmental changes in and around the Arctic region have been among the most pronounced changes related to climate change documented to date. Russia, situated squarely in the circumpolar north, continues to experience warming trends. One recent report in a journal called Polar Research, for example, showed an accelerated warming trend over Western Siberia between the years from 1966-1995.

More recent research from NOAA confirms those trends. According to a 2013 report:

A large increase in ALT was observed in West Siberia during 2009-2012, with 2012 ALT values being the highest (10% higher than 1995-2012 mean or 1.2 m) since 1996. A more or less continuous thickening of the active layer has been reported for Russian European North locations (Kaverin et al. 2012), where ALT in 2012 was the highest since observations began in 1998. Central Siberian locations also report the highest ALT values since observations began, in this case in 2005. In 2012 in eastern Siberia, ALT was 10% lower than in 2011 and all sites had lower ALT than the 1996-2012 average of 0.6 m. In 2012 in Chukotka (Russian Far East), ALT values were about 3% higher than in 2011, but overall there has been a progressive decrease in ALT since 2007, when it reached a maximum since observations began in 1994.

ALT or active layer thickness, refers to previously permafrost areas that warm up sufficiently for top layers of the soil to thaw from year to year.

Because sixty per cent of Russian land is categorized as permafrost, a soil condition defined by temperature, a warming climate could potentially change the Russian landscape.

Climate Change and Fracking

Recent research by a group from Cornell University suggests that hydraulic fracturing (fracking), the process used to extract natural gas from deep rock formations, could create substantially higher greenhouse gas emissions (GHG) than previously thought.

The authors honestly state upfront that their conclusions are tentative because the industry refuses to release statistics on methane emissions during the fracking process. For the sake of clarity in the current discussion, methane is the principle component of natural gas meaning it's almost correct to say methane=natural gas.

Cobbling together industry statistics from a variety of sources, the researchers also deliberately chose conservative estimates of methane gas emissions. They hope to improve on their current research with additional independent research sometime in the near future.

A video presentation of the research shows that it's rather straightforward, and easily understandable for the general public. Basically the researchers divided the natural gas extraction process into five phases:

  • during the initial flow back period
  • routinely and continuously at the well site
  • during liquid unloading
  • during gas processing
  • during transmission, storage and distribution

and then provided estimates for methane emissions at each step of the process

One interesting side note of the study deals with methane's global warming potential (GWP). Originally denoted as 20, or that it was twenty times more potent than carbon dioxide, the researchers say that methane GWP is closer to 100, and the next IPCC report will reflect that number.

© 2001-2016 Patricia A. Michaels