Impacts of Climate Change

The overall assessment of the projected climate change for North America by the IPCC, states specifically that the entire continent of North America is  "very likely to warm during this century, and the annual mean warming is likely to exceed the global mean warming in most areas. In northern regions, warming is likely to be largest in winter, and in the southwest USA largest in summer. The lowest winter temperatures are likely to increase more than the average winter temperature in northern North America, and the highest summer temperatures are likely to increase more than the average summer temperature in the southwest USA." (IPCC, 2013).  The part that I found most interesting was that most of the warming in the northern parts like Canada will increase more during the winter than in the summer.  I actually thought it would be the exact opposite.  The key factors of why this is happening is stated in section 11.5.1, where it says that "Central and northern regions of North America are under the influence of mid-latitude cyclones. Projections by AOGCMs (Chapter 10) generally indicate a slight poleward shift in storm tracks, an increase in the number of strong cyclones but a reduction in medium-strength cyclones over Canada and poleward of 70°N. Consequent with the projected warming, the atmospheric moisture transport and convergence is projected to increase, resulting in a widespread increase in annual precipitation over most of the continent except the south and south-western part of the USA and over Mexico" (IPCC, 2013).  This shows that the overall precipitation will increase as well.  Thus with increased temperatures and precipitation will happen mainly in the upper northern regions of North America, like Canada.  The middle region, or America, will have the opposite reactions but seem to be in harmony with the Keeling Curve. Just like the Keeling Curve suggests the entire continent of North America (along with the entire globe) will experience a clear and evident warming.

The IPCC's report on Working Group II: Impacts, Adaptation and Vulnerability show some extremely disheartening information with regards to North America as a continent.   It states that "Warming in western mountains is projected to cause decreased snowpack, more winter flooding, and reduced summer flows, exacerbating competition for over-allocated water resources. *** D [14.4, B14.2].  Disturbances from pests, diseases and fire are projected to have increasing impacts on forests, with an extended period of high fire risk and large increases in area burned. *** N [14.4, B14.1].  Moderate climate change in the early decades of the century is projected to increase aggregate yields of rain-fed agriculture by 5-20%, but with important variability among regions. Major challenges are projected for crops that are near the warm end of their suitable range or which depend on highly utilised water resources. ** D [14.4]" (IPCC, 2013).  In Colorado, which is a very mountainous region, we are already experiencing abnormal wild-fires that seem to be uncontrollable. As well as the insect problem mentioned in the above quote.  It only makes since that the increased heat caused a "decreased snowpack" and is exhausting our natural water resources.  This link http://www.nbcnews.com/video/nightly-news/52291488/#52291488 will take you to a video on NBC Nightly News with Brian Williams, which is in perfect harmony with the information collected by the IPCC.  One of NBC's reporters stated that the extreme wildfires in the U.S. are also experiencing "too many insects and not enough water" (NBC, 2013). Apparently, the wildfires now have spread to over six western states! It was also stated that in Canada they are experiencing historic flooding and rain. I wondered if this also has to do with the decreased snowpack, and it seems that it does, along with several problems in our Polar region.  The IPCC report states that "In the Polar Regions, the main projected biophysical effects are reductions in thickness and extent of glaciers and ice sheets, and changes in natural ecosystems with detrimental effects on many organisms including migratory birds, mammals and higher predators. In the Arctic, additional impacts include reductions in the extent of sea ice and permafrost, increased coastal erosion, and an increase in the depth of permafrost seasonal thawing. ** D [15.3, 15.4, 15.2] (IPCC, 2013). So, overall it looks like it is the result of too much heat; which is causing a cyclical effect causing everything in our polar regions to melt slowly.  Many cities like Calgary have been declared a disaster zone and evacuation is mandatory.  This is quite surprising because I have not heard about the massive floods in Canada until creating this blog.  This could be in part because the U.S. lame stream media decided to take global warming off of their main agenda, as it would eventually affect the profits of their major shareholders' oil reliant companies.

  

The Executive Summary for North America by the IPCC explains the overall situation of climate change for the entire continent.  The Summary made a very profound statement when it mentioned that “‘Mainstreaming’ climate change issues into decision making are a key prerequisite for sustainability".  Personally, I believe this is the biggest threat to the overall continent because the policies that Canada, America, and South America operate by cause a perpetual system of environmental destruction.  The policies used to back the oil based companies are so detrimental to our future generations that if there are not immediate changes implemented to find alternative sources of energy the damage will be non-repairable, as it already is.  The visual image that comes to mind is the Melting Permafrost Feedback chart, as well as the Ice Albedo Feedback chart from Module 1, section 5.  These two climate feedbacks will  have  a significant role in the overall climate change of Canada, along with prehistoric policies; the melting permafrost seems to post the biggest threat to Canada's climate.

The slide above shows the cycle of increased temperature causes the permafrost to melt, thus causing methane to be released and atmospheric concentrations increase, which then enhance the overall greenhouse effect.  This is what is known as a positive feedback, but will have an extremely negative outcome for Canada.  Just like in Colorado, as large glaciers (or permafrost) melts it will cause the flooding we now see in Canada, not to mention the increased greenhouse gas effect that is not the positive greenhouse gas effect.  However, based on research found at the National Science Foundations website (www.nsf.gov), it seems that sea level rise will significantly impact Canada and North America as a whole more than other continents due to the melting ice sheet in Greenland.  The NSF stated this in an article published in May of 2009 "The melting of the Greenland Ice Sheet this century may drive more water than previously thought toward the already threatened coastlines of New York, Boston, Halifax and other cities in the northeastern United States and Canada, according to new research."  They go on to say "A study in Nature Geoscience in March warned that warmer water temperatures could shift ocean currents in a way that would raise sea levels off the Northeast by about 20 centimeters (8 inches) more than the average global sea level rise that is expected with global warming. But it did not include the additional impact of Greenland ice, which at moderate to high melt rates would further accelerate changes in ocean circulation and drive an additional 10 to 30 centimeters (4 to 12 inches) of water toward northeastern North America on top of the average global rise." (NSF, 2009).

 Four to Twelve inches of water will definitely prove to be one of the most serious problem's North America will have to contend with.   The NSF also points out how this rise in sea level will affect the northward Atlantic conveyor belt “The northeast coast of North America is especially vulnerable to the effects of Greenland ice melt because of the way the meridional overturning circulation acts like a conveyer belt transporting water through the Atlantic Ocean. The circulation carries warm Atlantic water from the tropics to the north, where it cools and descends to create a dense layer of cold water. As a result, sea level is currently about 71 centimeters (28 inches) lower in the North Atlantic than the North Pacific, which lacks such a dense layer. If the melting of the Greenland Ice Sheet were to increase by 3 percent or 7 percent yearly, the additional fresh water could partially disrupt the northward conveyor belt. This would reduce the accumulation of deep, dense water. Instead, the deep water would be slightly warmer, expanding and elevating the surface across portions of the north Atlantic."(NSF, 2009).  This is eerily similar to the Younger Dryas period mentioned in Module 4.  The large concentration of freshwater caused a weak thermohaline circulation that completely stopped the ocean circulation casing a rapid cooling like the professor mentioned in the movie "The Day After Tomorrow" minus the Hollywood added Tsunami.  I see the connection here and I sincerely hope that the melting of Greenland does not cause a ice age type cooling like the Younger Dryas.  Although with all this increased warmth, I wonder if this rapid cooling would somehow create some sort of counter balance.  I am not sure how that would work, but it seems extremely daunting to say the least.

                                                            References:

·         Intergovernmental Panel on Climate Change, IPCC. (2013). Executive Summary; IPCC Fourth Assessment Report: Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability.  Retrieved from http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch14s14-es.html>

·         Intergovernmental Panel on Climate Change, IPCC. (2013). IPCC Fourth Assessment Report: Climate Change 2007: Working Group II: Impacts, Adaptation and Vulnerability.  Retrieved from <http://www.ipcc.ch/publications_and_data/ar4/wg2/en/spm.html>

·         NBC Network. (2013, June 23), NBC Nightly News with Brian Williams [Television series].  Retrieved from  http://www.nbcnews.com/video/nightly-news/52291488/#52291488

·         Intergovernmental Panel on Climate Change, IPCC. (2013).   IPCC Fourth Assessment Report: Climate Change 2007: Working Group I: The Physical Science Basis. (Sections 11.5.1, 11.5.2, 11.5.3) Retrieved from <http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch11s11-5.html>

·         National Science Foundation, NSF. (2009).  Press Release 09-110: Sea-level Rise May Pose Greatest Threat to Northeast U.S., Canada. Retrieved from <http://www.nsf.gov/news/news_summ.jsp?cntn_id=114871>