Celebrate World Ozone Day with NASA September 16th, 2014

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There are actually two kinds of ozone that scientists monitor – good ozone in our stratosphere that protects us from the sun and bad ozone in the troposphere that can impact our health.

What is ozone and why is some ozone “good” while some is “bad?” Just as humans need sunblock, the Earth needs protection too. Earth’s sunscreen is called ozone. The ozone that protects us, and all life on Earth, from the Sun’s harmful UV radiation is high in the atmosphere, in the stratosphere. But there is also ozone closer to Earth in the troposphere and that is harmful to the health of people, plants and animals.

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Satellite instruments monitor the ozone layer, and we use their data to create the images that depict the amount of ozone. This illustrates latest view of total ozone over the Antarctic pole using false colors. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone.

Decades ago scientists discovered that the Earth’s “good” ozone layer was thinning. It was being depleted by chlorofluorocarbons (CFCs), a group of chemicals used in everyday applications such as refrigeration, air conditioning and aerosols that were destroying the ozone molecules. But the international community came together with an agreement to vastly curtail the use CFCs.

In 1994, the UN General Assembly proclaimed September 16 the International Day for the Preservation of the Ozone Layer, commemorating the date of the signing, in 1987, of the Montreal Protocol on Substances that Deplete the Ozone Layer.

The theme for this year’s celebration is “Ozone Layer Protection: The Mission Goes On.” The Montreal Protocol has so far been successful in meeting some of its targets on phasing out ozone-depleting substances. As a result, the abundance of ozone-depleting substances in the atmosphere is declining and the ozone layer is expected to recover around the middle of this century. There are, however, some remaining challenges to the phase-out of ozone-depleting substances. NASA is also continuing to study ozone with instruments like OMI, Ozone Monitoring Instrument, the Ozone Mapping Profiler Suite (OMPS) on NPP, and, in 2016, SAGE III/ISS.

Without the ozone layer all of us on Earth would be exposed to more UV radiation, which could lead to problems like cataracts, cancer and reduced crop yields. Even with a recovering ozone layer it is important to protect yourself from Sun exposure by using sunscreen and sunglasses.

For more information and ways to join in the celebration visit the following links!

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