Led by NASA Goddard scientist Paul Newman, a team of atmospheric chemists simulated 'what might have been' if chlorofluorocarbons (CFCs) and similar ozone-depleting chemicals were not banned through the Montreal Protocol. The comprehensive model — including atmospheric chemical effects, wind changes, and solar radiation changes — simulated what would happen to global concentrations of stratospheric ozone if CFCs were continually added to the atmosphere.The visualizations below present two cases, from several different viewing positions: the 'world avoided' case, where the rate of CFC emission into the atmosphere is assumed to be that of the period before regulation, and the 'projected' case, which assumes the current rate of emission, post-regulation. Both cases extrapolate to the year 2065. ||

World Avoided Ozone Full AnimationThis video is also available on our YouTube channel. || world_avoided_robinson.1830_print.jpg (1024x576) [70.0 KB] || world_avoided_robinson.1830_searchweb.png (180x320) [38.8 KB] || world_avoided_robinson.1830_thm.png (80x40) [4.7 KB] || full_movie (1920x1080) [128.0 KB] || world_avoided_robinson_1080.mp4 (1920x1080) [26.3 MB] || world_avoided_robinson_1080.webm (1920x1080) [7.2 MB] || world_avoided_robinson_4272.pptx [27.2 MB] || world_avoided_robinson_4272.key [29.8 MB] || world_avoided_robinson_1080.mp4.hwshow [222 bytes] ||

Major sources of tropospheric NO2 include industrial emissions, automobile traffic, forest and brush fires, microbiological soil emissions, lightning, and aircraft. More than half of the total NO2 emissions are estimated to be anthropogenic, mainly from the burning of fossil fuels for energy production, transportation, and industrial activities. NO2 has a relatively short lifetime (about a day) and is therefore concentrated near its sources. ||

Montage of six measurements made by MLS || montage_early_data_aura_microwave_limb_sounder_print.jpg (1024x576) [59.6 KB] || montage_early_data_aura_microwave_limb_sounder_web.png (320x180) [40.8 KB] || montage_early_data_aura_microwave_limb_sounder_web.jpg (320x180) [11.6 KB] || montage_early_data_aura_microwave_limb_sounder_searchweb.png (180x320) [40.8 KB] || montage_early_data_aura_microwave_limb_sounder_thm.png (80x40) [4.4 KB] || mls_montage_720p.webm (1280x720) [1.3 MB] || mls_montage_720p.mp4 (1280x720) [1.3 MB] || mls_montage_1080p.mp4 (1920x1080) [2.3 MB] || montage_early_data_aura_microwave_limb_sounder.tif (5760x3240) [19.2 MB] || mls_montage_360p.mp4 (640x360) [523.1 KB] || mls_montage_2304p.mp4 (4096x2304) [6.4 MB] || Montage_early_data_Aura_Microwave_Limb_S.pptx [1.9 MB] || Montage_early_data_Aura_Microwave_Limb_S.key [4.3 MB] ||

The Microwave Limb Sounder (MLS) measures the chemistry of the lower stratosphere and upper troposphere. Ozone that is present in the troposphere is mostly a result of anthropogenic pollution and therefore higher concentrations are found in urban areas. ||

The Antarctic ozone hole reached its annual peak size on Sept. 11, according to scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA). The size of this year’s hole was 24.1 million square kilometers (9.3 million square miles) — an area roughly the size of North America.With the increased atmospheric chlorine levels present since the 1980s, the Antarctic ozone hole forms and expands during the Southern Hemisphere spring (August and September). The ozone layer helps shield life on Earth from potentially harmful ultraviolet radiation that can cause skin cancer and damage plants.The Montreal Protocol agreement beginning in 1987 regulated ozone depleting substances, such as chlorine-containing chlorofluorocarbons and bromine-containing halons. The 2014 level of these substances over Antarctica has declined about 9 percent below the record maximum in 2000.“Year-to-year weather variability significantly impacts Antarctica ozone because warmer stratospheric temperatures can reduce ozone depletion,” said Paul A. Newman, chief scientist for atmospheres at NASA's Goddard Space Flight Center in Greenbelt, Maryland.Scientists are working to determine if the ozone hole trend over the last decade is a result of temperature increases or chorine declines. An increase of stratospheric temperature over Antarctica would decrease the ozone hole’s area. ||

The Aura atmospheric chemistry satellite celebrates its 10th anniversary in July, 2014. Since its launch in 2004, Aura has monitored the Earth's atmosphere and provided data on the ozone layer, air quality, and greenhouse gases associated with climate change. ||

Visualizations of ozone concentrations over the southern hemisphere.Data is from ozonewatch.gsfc.nasa.gov ||

The next three decades will see an end of the era of big ozone holes. In a new study, scientists from NASA Goddard Space Flight Center say that the ozone hole will be consistently smaller than 8 million square miles by the year 2040.Ozone-depleting chemicals in the atmosphere cause an ozone hole to form over Antarctica during the winter months in the Southern Hemisphere. Since the Montreal Protocol agreement in 1987, emissions have been regulated and chemical levels have been declining. However, the ozone hole has still remained bigger than 8 million square miles since the early 1990s, with exact sizes varying from year to year.The size of the ozone hole varies due to both temperature and levels of ozone-depleting chemicals in the atmosphere. In order to get a more accurate picture of the future size of the ozone hole, scientists used NASA’s AURA satellite to determine how much the levels of these chemicals in the atmosphere varied each year. With this new knowledge, scientists can confidently say that the ozone hole will be consistently smaller than 8 million square miles by the year 2040. Scientists will continue to use satellites to monitor the recovery of the ozone hole and they hope to see its full recovery before the end of the century.Research: Inorganic chlorine variability in the Antarctic vortex and implications for ozone recovery.Journal: Geophysical Research: Atmospheres, December 18, 2014.Link to paper: http://onlinelibrary.wiley.com/doi/10.1002/2014JD022295/abstract.Here is the YouTube video. ||

LEAD: NASA scientists report that the ozone hole over Antarctica is slowly recovering.1. The ozone hole is the result of man-made chlorine and bromine chemicals reacting with thin ice clouds at 60,000 feet where temperatures are bitterly cold, less than –110 Degrees Fahrenheit.2. The ozone hole varies from twice to three times the size of the United States.3. Since the Montreal Protocol agreement in 1987, emissions have been regulated and ozone-depleting chemical levels have been slowly declining.4. With a new analysis, NASA scientists say that the ozone hole will be consistently smaller than less than twice the United States.TAG: Scientists will continue to use satellites to monitor the recovery of the ozone hole and they hope to see its full recovery before the end of the century. || WC_Ozone2040-1920-MASTER_iPad_1920x0180_print.jpg (1024x576) [115.0 KB] || WC_Ozone2040-1920-MASTER_iPad_1920x0180_searchweb.png (320x180) [78.1 KB] || WC_Ozone2040-1920-MASTER_iPad_1920x0180_web.png (320x180) [78.1 KB] || WC_Ozone2040-1920-MASTER_iPad_1920x0180_thm.png (80x40) [5.4 KB] || WC_Ozone2040-1920-MASTER_1920x1080.mov (1920x1080) [648.2 MB] || WC_Ozone2040-1920-MASTER_1280x720.mov (1280x720) [766.3 MB] || WC_Ozone2040-1920-MASTER_NBC_Today.mov (1920x1080) [241.4 MB] || WC_Ozone2040-1920-MASTER_WEA_CEN.wmv (1280x720) [17.3 MB] || WC_Ozone2040-1920-MASTER_converted.avi (1280x720) [19.0 MB] || WC_Ozone2040-1920-MASTER_baron.mp4 (1920x1080) [20.6 MB] || WC_Ozone2040-1920-MASTER_prores.mov (1920x1080) [518.5 MB] || WC_Ozone2040-1920-MASTER_iPad_960x540.m4v (960x540) [71.1 MB] || WC_Ozone2040-1920-MASTER_iPad_1280x720.m4v (1280x720) [116.2 MB] || WC_Ozone2040-1920-MASTER_iPad_1920x0180.m4v (1920x1080) [241.4 MB] || WC_Ozone2040-1920-MASTER_iPad_960x540.webm (960x540) [3.4 MB] ||