10th WMO/UNEP Ozone Research Managers Meeting

Geneva, 28-30 March 2017

Thailand

1.OBSERVATIONAL ACTIVITIES

1.1Column measurements of ozone and other gases/variables relevant to ozone loss.

Since 1979, Thai Meteorological Department (TMD)has carried out ozone observation with Dobson spectrophotometer No.90 in Bangkok under WMO/GAW programme. In 1996, two Brewer spectrophotometer (MKIV) No.121 and Brewer spectrophotometer (MKIV) No. 120 were additionally installed to measure total ozone, umkehr ozone profile, ultraviolet radiation and aerosol optical depth in Bangkok (13.667812°N, 100.605289°E) and Songkhla( 7.184520°N,100.604701° E)respectively. In 2009, TMD solar network in Bangkok was implemented further for ground-based measurements such as global/diffuse/direct/broadband UVA/UVB radiation, sky images, and physical properties of aerosols.

Figure 1.1 Station map for Dobson 90, Brewer 121 and Brewer 120

Another laboratory by Department of Physics, Faculty of Science, Silpakorn University (SU) has studied total ozone using Microtop ozonometer at Nakhon Pathom since 2010.

1.2Profile measurements of ozone and other gases/variables relevant to ozone loss

Umkehr ozone profiles have been measured withDobson#90, Brewer #121 and Brewer #120. Recently, a campaign for ozonesonde observations has been initiated with collaboration between Silpakorn University and Thai Meteorological Department using ECC sensors during January 2014- May 2015.

1.3UV measurements

UV measurements have been carried out by TMD in two GAW stations;

1.3.1. Bangkok, station number 216, Brewer #121,1996- present

A broadband UVA/UVB radiometer, during 2009-2015

1.3.2. Songkhla, station number 345, Brewer #120,1996- present

SU’s laboratory has also studied UV radiation at Nakhon Pathom using a Bentham spectroradiometerandUV Biometers (since 1998) and GUV-2511 radiometers have been used to monitoring ultraviolet radiation at Chiang Mai, Ubon Ratchathani, Nakhon Pathom and Songkhla (since 2008).

1.4 Calibration activities

With supports from WMO and JMA, Dobson #90 was taken to participate the

Inter-Comparisonat Tsukuba in 1996, 2006 and 2016. The Brewers were calibrated at Bangkok and Songkhla with Brewer#017 by IOS in 2005, 2008, 2009, and 2014.

2. RESULTS FROM OBSERVATIONS AND ANALYSIS

A figure show long term trend for total ozone measured in Bangkok during 1980-2016.

Figure 2.1. Daily average of total ozone measured with Dobson No.90 in Bangkok

A study has compared total ozone measurements with Dobson, Brewer OMI and ozonesonde and showed the result of seasonal variation and consistency as the figure below:

Figure 2.2. Seasonal daily variation of various quantities during the period 01/01/2014 to 31/05/2015 at the study site (13° 39′ 58.57″ N, 100° 36′ 21.44″ E): A) Daily column ozone obtained from Dobson spectrophotometer, Brewer spectrophotometer, ozonesonde and OMI/AURA satellite.

Figure 2.3. Ozone soundings showing mixing ratios in the bottom 3000 m of the atmosphere for A) the wet season from May-October, 2014 and B) the dry season from November 2014 to April 2015. Circles denote localised maxima.

3. THEORY, MODELLING, AND OTHER OZONE RELATED RESEARCH

There were investigating studies for total ozone and UV prediction. A study in 2004 were related to empiricallyerythemal UV models which using ground-based Dobson and/or Brewer spectrophotometer and TOMS/OMI ozone data, aerosol optical depth and other meteorological parameters as inputs forUV calculation. The empiricalhas been used coupled with radiative transfer (STAR) model inoperational UV index forecasting.

4.DISSEMINATION OF RESULTS

Results of monitoring of ozone, solar UVradiation and others are disseminated to data centers, governmental and private sectors, educational institutes and public by documentary and in a website (

4.1Data reporting

Dobson and Brewer data are regularly submitted to World Ozone and Ultraviolet Data Centre by monthly. Solar radiation is submitted to World Radiation Data Centre. Sky radiometer raw data are submitted to SKYNET (

4.2Information to the public

UV index forecasts are published in a website:

Figure 4.2. UV index forecast for Thailand (

4.3Relevant scientific papers

4.3.1Janjai et al. (2016) Meteorological factors affecting lower tropospheric ozone mixing ratios in Bangkok, Thailand Journal of Atmospheric and Solar-Terrestrial Physics 147, P. 76–89.

4.3.2Sudhibrabha S, Exell RHB, Sukawat D (2006) Ultraviolet Forecasting in Thailand, ScienceAsia Vol. 32 No 2, pp. 107-114.

4.3.3Sudhibrabha S, Exell RHB, Sukawat D (2004) Preliminary Forecast of Ozone and UV over Thailand, Proceedings of the XX Quadrennial Ozone Symposium, 1-8 June 2004, Kos, Greece, pp. 1157-1158.

4.3.4Vanichnukroh P, Sukawat D, Sudhibrabha S (2004) Ozone Profile in the Climate of Thailand, Proceedings of the JGSEE and Kyoto University Joint International Conference on "Sustainable Energy and Environment (SEE)", 1‐3 December 2004, Hua Hin, Thailand.

5.PROJECTS, COLLABORATION, TWINNING AND CAPACITY BUILDING

Mission in ozone monitoring and research in Thailand has been responsible by TMD. There isalso collaboration with universities in particular projects.

For capacity building, some staffs from TMD received financial support from WMO in participating the 14th WMO-GAW Brewer User’s Workshop, 24-28 March 2014 in Santa Cruz, Tenerife and and 15th EUBrewnet & WMO-GAW Brewer Operator Course,4-9 September 2016, Edinburgh. Some were supported in participating the 8th GAWTEC in 2004 and 10th GAWTEC in 2005.

6.IMPLEMENTATION OF THE RECOMMENDATIONS OF THE 9th OZONE RESEARCH MANAGERS MEETING

There were some difficulties that interrupted continuation or delay of ozone data submission to WOUDC due to instrumentation problems especially Brewer spectrophotometer. These problems are to be improved.

7.FUTURE PLANS

Public sectors have raised more questions and interests on ozonechanging and UV levels. TMDhas a strategyto strengthen public service relating to high level of solar UV, its impacts and health protection.

TMD will extend the Brewer network to be covered four regions of the country in the next few years.

There is a research project to improve ozone and UV forecasting and development a mobile App for users.

8.NEEDS AND RECOMMENDATIONS

Although the government has capability to support ozone and UV monitoring activities, implementation by the Trust Fund for Dobson/Brewer Inter-Comparison/calibrations and educational trainingwould behighly appreciation.Additionally, TMD’s working team should to join closer working with the ozone community. TMD would encourage and welcome external experts or partnership.

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