- Abstract:
-
Stratospheric Ozone level for October 5, 1987.
- Subject:
- Science and Technology
- Grade Level:
- Secondary, Post-secondary
- Collection:
- NASA GSFC Scientific Visualization Studio
Stratospheric Ozone level for October 5, 1987.
Stratospheric Ozone level for September 19, 1988.
Stratospheric Ozone level for October 7, 1989.
Stratospheric Ozone level for October 4, 1990.
Stratospheric Ozone level for October 5, 1991.
Stratospheric Ozone level for October 10, 1992.
Stratospheric Ozone level for September 28, 1994.
Stratospheric Ozone level for October 5, 1996.
Stratospheric Ozone level for September 24, 1997.
Stratospheric Ozone level for September 30, 1998.
Stratospheric Ozone level for October 1, 1999.
Stratospheric Ozone level for September 26, 2001.
Zoom in to Montana fires on August 8, 2000 showing the correlation between aerosols as measured by Earth Probe TOMS and smoke plumes as seen by SeaWiFS
The Erythemal Index is a measure of ultraviolet (UV) radiation at ground level on the Earth. (The word erythema means an abnormal redness of the skin, such as is caused by spending too much time in the sun--a sunburn is damage to your skin cells caused by UV radiation.) Atmospheric ozone shields life at the surface from most of the harmful components of solar radiation. Chemical processes in the atmosphere can affect the level of protection provided by the ozone in the upper atmosphere. This thinning of the atmospheric ozone in the stratosphere leads to elevated levels of UV at ground level and increases the risks of DNA damage in living organisms.
This visualization shows the total ozone concentrations for the Earth from January 1, 2000 through December 31, 2003, as measured by the Toms instrument on the Earth Probe satellite. Low ozone (less than 200 Dobson units) is depicted as regions of dark blue, with high ozone (greater that 330 Dobson units) depicted as yellow and red. The most visible and dynamic feature of the ozone distribution is the ozone hole that forms over Antarctica during September of each year. The amount of ozone in the stratosphere over Antarctica is reduced during this period due to unique atmospheric conditions which chemically reduce the amount of ozone in the region and prevent that ozone from mixing with the higher ozone concentrations just outside the hole. Ozone blocks harmful ultraviolet B rays, and loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects in plants and animals. This visualization explicitly shows the TOM ozone data coverage and does not interpolate data into regions of the Earth that the instrument did not observe. Since TOMS measures ozone by observing the characteristics of sunlight reflected from the Earths surface, no measurements are available for the poles during the polar winter, i.e., around January for the North Pole and July for the South Pole. Also, there is an unobserved region between successive satellite orbits around the equator. Finally, the instrument has periods where technical issues make measurement impossible for a matter of hours or days. This visualization shows that the dynamics of the ozone layer remain visible despite these measurement issues.
This ozone hole animation was created for the panel session Astrophysics or Astro-graphics at the workshop Communicating Astronomy to the Public on October 2, 2003. The purpose of the animation was to illustrate two different ways that a visualization might be structured based on the amount of time the viewer had to look at it. The animation on the left fully illustrated the data, imperfections and all, under the assumption that a presenter would have time to explain the animation in detail. The animation on the right had all the data imperfections removed by interpolation, under the assumption that the viewer would only have 20 or 30 seconds to look at it (on the evening news, for example) with only the briefest of explanations. The problem was that, without explanation, a layman might interpret the region of missing data in the movie on the left to be the ozone hole, instead of the central blue region. The point was that the truth of a visualization lies in the mind of the beholder, not in the absolute content of the imagery.
For more information and images see (http://svs.gsfc.nasa.gov-stories-toms-) or animations 2619 and 708.
The peak of the Antarctic Ozone Hole in 1999, as measured by Earth Probe TOMS on September 15, 1999.
Polar stratospheric clouds form at extremely low temperatures in the upper atmosphere. Should the temperature rise, clouds wont form. In this visualization, sequential temperature readings taken in the research area for SOLVE (Stratospheric Ozone Loss and Validation Experiment) are plotted against a threshold temperature for PSC formation. These are clouds essentially made of nitric acid. Note how the area covered by the clouds increases as winter progresses. The red point on the map indicates the location of Kiruna, Sweden, the SOLVE staging area.
The fires that raged across southern Africa in August and September of 2000 produced a thick river of smoke that observers compared with the aftermath of the Kuwaiti oil fires in 1991. NASA-supported studies currently underway on the event will contribute to improved air pollution policies in the region and a better understanding of its impact on climate change.