|
Current global warming trends are impacting the Arctic, causing permafrost to melt. Contained under permafrost are methane clathrates, which contain large volumes of methane, a damaging greenhouse gas. Ice core data evidence from 55.5 million years ago suggests organism extinctions from rapid clathrate methane release. Today global warming trends are beginning to release methane clathrates, and there is a large potential in the future for these methane reserves to begin another rapid global warming period.
|
|
A rising concern in climate change involves the possibility of methane hydrates (or clathrates) contributing to global warming. Most clathrate reserves are sheltered under permafrost, making them vulnerable to climate change. Even though climate change is a natural phenomenon, clathrates will accelerate global warming because of rapid surface temperature variations, which is evident from past ice core data. Understanding the rate of permafrost melt is essential to mitigate global warming potential due to the large amounts of dangerous greenhouse gases it protects.
|
|
Today the United States' government is documenting surface temperatures, and has been doing so since the 1850’s. Methane rapidly increases in a warming climate with a small lag behind temperature (Schmidt, 2004). A rise in global mean surface temperatures between 1.0oF and 1.7oF has been documented in the past 150 years (EPA, 2008). There has been a rapid rise in the average surface temperatures of about 1.0oF since the 1970’s (NOAA, 2008). Today’s current trends show a rise of 0.32oF every decade, which calculates out to be 3.2oF every century. The increased temperatures have led to the eight warmest years on United State record occurring since 1998 (Figure 2), with 2005 being the warmest year (Hansen, 2007). |
|
|
Permafrost is characterized by areas of soil which stay frozen (0oC) year round, for at least two years (Perkins, 2007). Since permafrost can only be sustained in temperatures below the freezing point, it is only found near the poles. Currently, permafrost covers thirty percent of the Earth’s terrestrial surface (Arain, 2007). The arctic is believed to be the most susceptible area to climate change (Arain, 2007) so, permafrost survival becomes a problem. When large areas of permafrost melt, it unveils clathrates to the sun allowing them to melt, unleashing methane gases. Global
temperatures are rising rather quickly, but Arctic
temperatures are rising at a faster pace compared to the mid
latitudes (Costa,
2007). The
Arctic air temperatures are believed to have increased at
almost twice the global rate in the past 100 years
(EPA,
2008).
Alaska and western Canada’s average summer temperatures
have increased by about 1.4oC since 1961 (Perkins,
2007).
There has been a widespread reduction in the number of days
below freezing, ultimately causing the melting of permafrost
in the Polar Regions. Some models predict that permafrost
will decline from four million (Figure
3) to only
one million square miles by the year 2050 (National
Center for Atmospheric Research,
2005).
Other recent studies in Sweden show a direct methane
increase between 20%-60% in 30 years from permafrost thawing
(Schmidt,
2004).
|
|
|
Clathrates are cages of water molecules which house methane gases. Permafrost creates the correct conditions of low temperature and high pressure to trap methane gas generated from decomposing matter under permafrost (Kerr, 1999). Methane is a powerful greenhouse gas which is at least twenty times more potent than carbon dioxide in trapping heat (Costa, 2007). Some estimates predict up to 10,000 gigatonnes of methane are stored in clathrates (Schmidt, 2004). Clathrates reside in permafrost and exist in continental margins. All of the methane gas in permafrost and continental margins totals three times more methane that exists in the present-day atmosphere (USGS, 2007). The danger of methane escaping from clathrates occurs when permafrost cliffs erode (Figure 4), or permafrost melts exposing clathrates to warm temperatures, thus releasing their gases. The decrease in summer ice cover in the Arctic can increase wave action on the shores, thus release these stocked up clathrates into the ocean (Perkins, 2007). Luckily, today only five percent of the world’s methane emissions come from clathrates (Kerr, 1999).
|
|
|
Large clathrate deposits are thought to have influenced global climate change (Kerr, 1999). There is a current debate over the “Clathrate Gun Hypothesis”, which is used in attempt to explain the environmental changes during the end of the Paleocene epoch, 55.5 million years ago (Schmidt, 2004). The theory states methane hydrates dissociated once a critical point is reached in the atmosphere ocean system following a prolonged period of global warming in the Eocene epoch (Kerr, 1999). Evidence gained from examining ice cores shows that methane was released in a short time period changing temperatures drastically. This rapid release of methane created a direct rise in surface temperature (Figure 5) of 3oC to 4oC (Schmidt 2004). This is known as the Paleocene-Eocene thermal maximum (PETM) which caused the extinction of almost 50% of the calcareous benthic foraminifera (Kerr, 1999). The "Clathrate Gun Hypothesis" is not accepted by all scientists. Some reject this theory because of lags in temperature changes, and the magnitudes involved do not appear large enough to contribute to methane (Schmidt, 2004). Another explanation for the rapid change during the PETM is from increased rain in the tropics, and thus it increases emissions from tropical wetlands which was large enough to increase methane sinks (Schmidt, 2004). There is still a lot of research which needs to be done on methane cycles during the ice ages, so hydrates may be considered apart of the reasoning behind rapid climate change (Schmidt, 2004). |
|
|
|
The United States has some of the world’s largest hydrate reserves. With growing energy demands, the government has decided to look towards the future in trying to extract the gas caged in hydrates. President Bush (Figure 6) is in favor of clathrate exploration. The Methane Hydrate Research and Development (R&D) Act of 2000 was enacted to give money towards the exploration in mining for clathrates. Money from the government is given out to agencies in order for them to study methods of extracting methane from these hydrates since it is extremely difficult. There is a Methane Hydrate Advisory Committee which consists of 12 members with backgrounds representative of industry, academia, and government (The National Academies Press, 2008). Under this legislation the Department of Energy (DOE), is in charge of the research. |
|
To read more on the methane hydrate research policies please visit:
|
These studies suggest apparent climatic shifts resulting from rapid greenhouse gas release. Only recently has permafrost started to melt rapidly, but if predictions are correct, permafrost will diminish. The exact volumes of methane locked in clathrates is unclear, but the danger lies in releasing these natural reserves to find out. Slowing down permafrost melt is difficult since it relies on global average temperatures. The warming climate dilemma is a never ending loop of ice melting from temperature change, which is being accelerated from the escape of methane gases (Figure 7). Ice core evidence shows rapidly released methane is extremely dangerous since it changes climate at a rate where organisms cannot evolve in order to survive. Since evidence of clathrates accelerating global warming is now available, it is essential to take these warnings into consideration for future climate sustainability.
|
|
|
The government wants to tamper with this natural reserve which is extremely dangerous. People all over the world are striving to find new energy sources, but the answer should not lie in tampering with hydrates. It is important for future scientific study to better understand their potential impact on climate. If you would like to support the researchers working towards understanding clathrates potential impact on the environment please send this letter to one of the following researchers. Dr. William Dillion If you are concerned with the government’s exploration of clathrates as a potential future energy source, please send this letter to the main researchers of the DOE who is involved with the mining of clathrates. U.S. Department of Energy |
Arain, Altaf, (2007). Peat and Forests Save Permafrost From Melting. ScienceDaily. Retrieved on 1 April 2008 from http://www.sciencedaily.com/releases/2007/09/070913132927.htm.
Costa, Anna, 2007. The Science of Climate Change. Ecologist 37: 10-16.
Edwards, R., N., Marine Electromagnetic Methods Accepted for Exploration!. Retrieved on 28 March 2008. from http://www.physics.utoronto.ca/~edwards/.
Environmental Protection Agency (EPA), 2008. Temperature Changes. Retrieved on 28 March 2008. from http://www.epa.gov/climatechange/science/recenttc.html.
Greenpeace, 2005. Greenpeace Response to Bush's Speech. Retrieved on 28 March 2008. from http://www.greenpeace.org.uk/media/press-releases/greenpeace-response-to-bush-speech.
Hansen, James, E./ NASA, 2007. GISS Surface Temperature Analysis. Retrieved on 28 March 2008. from http://data.giss.nasa.gov/gistemp/2007/.
Kerr, Richard, A., 1999. Climate Change: A Smoking Gun for an Ancient Methane Discharge. Science 286: 146-148.
Lawrence, David, 2005. Permafrost Meltdown Across the Arctic. Retrieved on 1 May 2005. from
www.ens-newswire.com/.../
National Center for Atmospheric Research (2005). Most of Arctic's Near-surface Permafrost to Thaw By 2100. ScienceDaily. Retrieved 1 April 2008 from http://www.sciencedaily.com/releases/2005/12/051220085054.htm
National Oceanic and Atmospheric Administration (NOAA), 2008. Climate of 2007 - in Historical Perspective Annual Report. Retrieved on 28 March 2008. from http://www.ncdc.noaa.gov/oa/climate/research/2007/ann/ann07.html.
Nourse, Stephen, 2000. Melting Permafrost in the Arctic. Retrieved on 31 January 2008. http://www.alaska-in-pictures.com/melting-permafrost-1962-pictures.htm.
Perkins, Sid, 2007. Not-So-Perma Frost. Science News 171: 154-156.
Rath, Bhakta, B., 2005. Abundance of Frozen Clean Energy from the Sea. Retrieved on 28 March 2008. from http://www.nist.gov/public_affairs/colloquia/20050121.htm.
Schmidt, Gavin/NASA, 2004. Methane: A Scientific Journey from Obscurity to Climate Super-Stardom. Retrieved 28 March 2008 from http://www.giss.nasa.gov/research/features/methane/.
The National Academies Press, 2008. Scientific Oversight of the DOE Methane Hydrate Research and Development Program. Retrieved 28 March 208 from http://books.nap.edu/openbook.php?record_id=11094&page=83.
United States Geological Survey (USGS), 2007. Losing Permafrost. Retrieved on 12 February 2008. http://carbon.wr.usgs.gov/lostpermafrost.html.
