Shrinking the Ozone Hole

           In 2012 the Antarctic Ozone Hole was reported by NASA to be the second smallest size it has been in 20 years.  It had reached it largest size on record Sept. of 2000 at 11.5 million square miles.  It also recorded a minimum value of total ozone that year recorded as the second highest overall level in two decades.  The ozone hole was monitored for the first time by the Suomi National Polar-orbiting Partnership (NPP) satellite using an instrument called the Ozone Mapping Profiler Suite (OMPS).  NOAA along with NASA have a mandate under the Clear Air Act to monitor ozone-depleting gases alone with stratospheric depletion of ozone and does so with ground and satellite measurements.  You can monitor the ozone later above Antarctica with this link!

Human, Katy. "NASA - 2012 Antarctic Ozone Hole Second Smallest in 20 Years ." NASA - Home. N.p., 24 Oct. 2012. Web. 12 May 2013. <http://www.nasa.gov/home/hqnews/2012/oct/HQ_12-371_2012_Ozone_Hole.html>.

Radiative Forcing

     Radiative forcing (RF) describes the difference between the energy that is gained by Earth and then later lost to space.  The IPCC uses radiative forcing with assessments, “to denote an externally imposed perturbation in the radiative energy budget of Earth’s climate system, which may lead to changes in climate” (Braun, 2013).  Greenhouse gas concentration can change and cause a disturbance in the radiative forcings that are calculated.  It is used to assess and compare natural and human related drivers of climate change.  It ranks and quantifies the different influences of climate change but doesn’t represent overall climate responses (IPCC, 2007).

     Radiative forcing can be related to the greenhouse effect as well, both natural and human enhanced.  The imgage belshows a number of radiative forcing drivers, the first two bars, both red, are greenhouse gases, mainly driven by human forces.  Both of these have a large radiative forcing affects.  CO₂ emissions cause an increase of RF.  This is due to the fact that carbon dioxide influences the amount of heat that is captured within the atmosphere.  The more heat that is captured due to that specific greenhouse gas, which is influenced by human activities such as driving cars, the higher the radiative forcing bar for that driver.  The third bar that is shown depicts ozone RF, depending on the good or bad ozone there is either a negative or positive RF, which can also be affected by human activities.  

A simple graph showing the components of radiative forcing.  Bars in red show where heat is added while bars in blue show cooling influences.  Heating affects have positive values, while cooling affects have negative values.

Braun, Carsten. 2013. The Concept of Radiative Forcing. Handout.

IPCC. 2007. "2.2 Concept of Radiative Forcing - AR4 WGI Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing." IPCC - Intergovernmental Panel on Climate Change. N.p., n.d. Web. 22 Feb. 2013. <http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-2.html>.

It's Good. It's Bad. It's Ozone

The ozone and climate change are connected to one another here on Earth.

                             There are two different types of ozone, the good ozone and the bad ozone.

            The good ozone, located in the stratosphere, creates a sort of shield that protects us from the harmful UV rays that enter Earth’s atmosphere.  The UV radiation, instead of penetrating down to Earth, is converted into heat through a molecular reaction of ozone being split apart, but is continually re-joined with other oxygen molecules, thus forming an ‘ozone-oxygen cycle’.  Human-made compounds such as chlorofluorocarbons (CFCs) that are added to the atmosphere cause an even greater breakup of ozone and allow more UV radiation to get down to earth (The Good, the Bad and the Ozone, 2013). 

            Bad ozone can be found in the troposphere, which is where life on Earth is found.  Ozone in the stratosphere can cause lung damage to humans.  One of the biggest contributors to harmful emissions in our breathing air is car exhaust (The Good, the Bad and the Ozone, 2013).  Bad ozone can also damage crops and other vegetation that cycle carbon dioxide in our air (EPA).

            Back in 1974 it was discovered that CFCs were in the stratosphere destroying ozone molecules.  A thinning of the ozone layer above Antarctica caused an urgency to stop production of CFCs and led to the creation of the Montreal Protocol, phasing out CFC use and stopping the hole from becoming larger (Doniger, 2012).  Solomon and Chanin (2011) talk about how CFCs along with other greenhouse gases deplete ozone, but also contribute to climate change.  With more ultraviolet light able to reach Earth’s surface there can be damage to plants and animals DNA.  Overall, with the ozone thinning and more heat energy becoming trapped in the atmosphere of the Earth an overall warming affect is likely to happen (Solomon, 2011).

Doniger, David. "The world's governments saved the ozone layer. They can save the climate too. | David Doniger - China Dialogue ." China Dialogue - China and the world discuss the Environment . N.p., 11 June 2012. Web. 10 Feb. 2013. <http://www.chinadialogue.net/article/show/single/en/5295-The-world-s-governments-saved-the-ozone-layer-They-can-save-the-climate-too->.

EPA. "Ozone - Good Up High Bad Nearby | Air Quality Planning & Standards | Air & Radiation | US EPA." US Environmental Protection Agency. N.p., n.d. Web. 21 Feb. 2013. <http://www.epa.gov/oaqps001/gooduphigh/>.

Solomon, Susan and Chanin, Marie-Lise. 2011. The Antarctic Ozone Hole: A Unique Example of the Science and Policy Interface. Science Diplomacy. 189-195.

“The Good, the Bad and the Ozone”. Handout. 2013. <http://earthsobservatory.nasa.gov/Features/Ozone/Ozone.php>. and <http:http://www.nasa.gov/missions/earth/f-ozone.html>.