These introductory remarks to climate change need a rewrite.
Climate change or global warming is based on a very simple hypothesis. Anthropogenic (human caused) emissions of greenhouse gases (GHGs) contribute a layer of gases around earth’s atmosphere. The accumulation of GHGs then blocks some of earth’s emanating heat from escaping to space, causing a general heating or global warming pattern.
The global scientific and political community, under the direction of the United Nations Framework Convention on Climate Change (UNFCCC) identifies six primary greenhouse gases.
- carbon dioxide (CO2)
- methane (CH4)
- nitrous oxide (N2O)
- hydrofluorocarbons (HFCs)
- perfluorocarbons (PFCs)
- sulphur hexafluoride (SF6)
Considerations about the degree to which GHGs influence climate change deal with two sets of issues. Aggregate emissions trends estimate the volume of each of the six GHGs released into the atmosphere per year. Of equal importance is the relative power of the various GHGs to act as atmospheric road blocks that keep heat in the atmosphere.
Scientists call this road blocking ability the Global Warming Potential (GWP) of a gas. The standard measurement unit is 1 for Carbon, and it turns out Carbon is the least effective of the GHGs in trapping earth’s heat.
For comparative purposes, over a twenty year time span, Methane’s GWP=56, Nitrorus Oxide’s GWP=310 and the GWP of the engineered chemicals varies from 460-16,000 (see UNFCCC Global Warming Potential).
Each GHG also has a life span, or time it remains stable in the atmosphere. Whereas the numbers for carbon look somewhat benign in terms of its GWP, they start to look a bit more daunting when considered in terms of life span. Scientists estimate that CO2 remains stable in the atmosphere for anywhere from 50-200 years. Methane, on the other hand, remains stable only about 12 years. Nitrous Oxide’s life span reaches the 120 year mark. Finally the engineered chemicals may remain stable for anywhere from 2 to 50,000 years for Perfluoromethane.
Scientists researching climate change use General Circulation Models GCMs. Generally speaking, they are statistical global weather forecasting models. Sometimes the phrase coupled models is associated with GCMs. That means the models integrate ocean elements and atmospheric elements, in order to more accurately describe, explain and predict global climate patterns.
Climate scientists often check on The Reliability of GCMs to improve on their long term climate predictions. In the most general terms, the GCMs have predicted that the polar regions would experience the most stark weather changes, especially with increased temperatures.
That prediction has been partially true, especially for the circumpolar north. The next section provides information on climate patterns in the polar regions.
Climate Change and the Polar Regions
Climate change in the polar regions, north and south cause a few concerns. First and foremost they hold a good deal of the world’s ice. Warming polar regions translates into melting ice and consequently sea level rise.
Changing polar climates also means that the wildlife that inhabits the areas, especially the circumpolar north such as Polar Bears and the Pacific Walrus face environmental challenges that will cause high levels of population stresses.
Here’s a quick run don of some recent climate happenings in the 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 are mirror images of 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 continues 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.
The research is especially interesting because of the current push for fracking in the Arctic Ocean area. Increased methane releases into the atmosphere can increase the rate of permafrost loss.