monitoring of ozone layer and some research results in Mongolia
National Report by
Professor AdiyasurenTs.
Counselor to the Minister of Environment and Green Development of Mongolia and Director of the National Ozone Authority
Phone: 976 11 312458
976 99192160
E-mail: ;
Introduction
This report includes briefing of the observation and research studies of ozone layer protection in Mongolia. Themeasurement of ozone from ground based stationsin Mongolia has started since 2010.
The total column ozone from rocket was measured in between 1988 to 1992.
For the recent yearsthe total column ozone was measured with data from Nimbus satellite from 1979 to 1992 and Aqua and Terra satellites from 2007 to 2013.
Ozone layer observation and research
- The measurement from ground based station
The ground based measurement station O3-42Mwas established in Ulaanbaatar, Mongolia in 2010 with the support of France.
- At ozone sounding level
There is no available ozone sounding for studying the ozone layer level.
- The observations from rocket
In cooperation with Russia, the measurement station from rocket was operated during 1988 to 1992in Sainshandcityof Dornogobi Province.
Sainshand city (coordination of N 44°53'28.38", E 110°08'11.32") is located in the southern gobi region in Mongolia.
With the M-124 ozonometer from Russia the total ozone was measured. The status of tropopause was determined with the aerologic data at the same time. The measurement from rocket had operated until 1992.
- The satellite observation and remote sensing
In Mongolia, the measurements from ground based station did not provide much information, and it was experimented on satellite data. Data from the TOMS on the Nimbus 7 satellite were obtained from NASA database and were used to measure the total ozone distribution in between 1979 and 1992.
In addition, data from MODIS sensoron the Aqua and Terra satellites were used to measure the total ozone distribution in Mongolia.
Further it is possible to monitor with the satellites data.
The research conducting authorities
-Institute of Meteorology and Hydrology, Mongolia
-Information and Computing Center, Ministry of Environment and Green Development of Mongolia
-National Ozone Authority, Ministry of Environment and Green Development of Mongolia
Data and methodology used in the research
Data from the TOMS on the Nimbus 7 satellite were used to measure the total amount of ozone in Mongolia.The MODIS sensor provides high radiometric sensitivity in 36 spectral bands ranging in wavelength from 0.4 µm to 14.4 µm.Terra MODIS and Aqua MODIS are viewing the entire Earth's surface every 1 to 2 days, acquiring data in 36 spectral bands, or groups of wavelengths. These MODIS instruments will offer an unprecedented look at terrestrial, atmospheric, and ocean phenomenology for a wide and diverse community of users throughout the world.
Figure1. Total Ozone Distribution over theMongolia, by Dobson Unit
The measured total ozone is reported in Dobson Units (DU), and the value is in between 0 to 500.
Value = scale factor *0.1
Results of ozone research
Reliable observations and research of ground based measurements and ozone zone being unavailable in Mongolia, the earlier research studies were done with data from aircrafts. In recent years, data from satellites were used to measure the ozone level above Mongolia.
Spatial and temporal distribution of ozone
The progress of monthly data rocketmeasurements from Sainshand station in 1989 is shown on figure 2.
The content of total ozone was instable, and the difference between the days in any month was greater.
Figure 2. The progress of monthly data measurements /Sainshand station, 1989/
Figure 3. The monthly average content of the total ozone / Sainshand /
According to the monthly average total ozone, the ozone content was higher during winter and spring in Gobi regions and lower in summer and autumn.
Figure 4. The progress of multi annual total ozone / TOMS data /
According to TOMS satellite data coverage in Mongolia / the northern latitude of 35.5°-55.5° and the eastern longitude of 80°-130°/, its average shows that the total ozone decreased during 1979 to 1999. But it was predicted that it might increase in the last 5 years.
According to the measurements of Sainshand station, the average value for the last 4 years predicted that there might be increase. At the same time, the satellite data showed the similar results.
Figure 5. The progress of multi annual total ozone / TOMS data /
According to the variation of multi annual contents of the total ozone, it decreased continuously, and its lowest value reached in 1993 to 1994.
When the total ozone content is compared to the tropopause height, the ozone content increases with the decrease of tropopause height.
Figure 6.The total ozone contents and tropopause height
Figure 7. The total ozone contents and tropopause temperature
The total ozone content is higher when tropopause temperature is lower.
In the research, the result of data from the following satellite is included.
The average value from satellite data of 1978-1993,by Dobson Unit is shown in the figure 8.
Figure 8. Distribution of total ozone over Mongolia
Duetodissimilar existence ofhighmountains suchasAltai, KhangaiandKhentii, steppeandgobiregion thetotal ozone distribution hasitsevidentcharacteristic. Itisvery important toanalyze carefully the spatial and temporal distributionoftotal ozone over Mongolia. This isvery significant for understanding the regional climatic feature of Mongolia.
FromFig.9 wecanseedistribution oftotalozone ofMongolia presents latitudinal distribution generally.
Figure 9. The long time trend of total ozone overMongolian territory
FromlongtimechangetrendsofNovember1978to April 1993oftotal ozone (Fig.9), bothlatitudinal and longitudinal averagesoftotalozonehaveslowdecreasing trend.Themaximumdecreaseoflatitudinalaverageappearsin1987andin1985. Thelongitudinalaveragevariessmoothlyandsteadily.
Longtermchangetrendsofseasonal totalozoneinSainshandindicates thatthemost obvious decrease of total ozone occurs inwinter (January), then summer (July) the relevantlowchangesoccursinautumn(October)andthespring(April).ItisshowninFig.10.
Figure 10. The seasonal trend of latitudinal average of total ozone over Mongolia
MODIS data from Aqua and Terra satellites have been extracted and processed daily since 2008 in Mongolia. With these provided data, the total ozone content in Mongolia between 2008 and 2013 were studied.
The trend of the total ozone content over Mongolian territory and Sainshand area by the average value of January, April, July and October between 2008 and 2013 is shown in figures 11-14.
Figure 11. The average ozone content in January
Figure 12. The average ozone content in April
Figure 13. The average ozone content in July
Figure 14. The average ozone content in October
According to the research on seasonal average in 2008 to 2013, the result showed ozone level is decreasing in every season over Mongolian territory.
Conclusion
Since 1988, the observation and measurement of ozone from rockets had started in Mongolia. We have the opportunities to monitor the ozone level with the satellite data under our available financial and economic conditions.
We attempted to describe the progress of monthly, annual and multi annual ozone contents over Mongolian territory comparing the results from the total ozone and aerologic measurements of Sainshand station between 1988 and 1992 and the rocket data.
It clearly showed that the ozone content in the stratosphere was instable, and it changed daily. The ozone content over Mongolian territory was higher in winter and spring, lower in summer and autumn. According to the satellites data from 1979 to 1999 and from 2008 to 2013, the total ozone level appeared to be decreasing.
Reference
- Report of the fifth meeting of the ozone research managers of the parties to the Vienna convention for the protection of the ozone layer. WMO, UNEP, Geneva, 25-27 March 2002.
- European research in the stratosphere 1996-2000, European commission -2001, Ozone volume I Athens, Greece 2004
- AdiyasurenTs.,Bujidmaa B. Distribution of Ozone over the Mongolia.-Research Report.Ulaanbaatar. 2005
- Oyunchimeg. Some Analysis ozone Distribution in Mongolia. – Conference on Ozone Layer Protection, Ulaanbaatar, 2007.