The Tibetan Plateau has the most prominent and. Climate change and related weather/environmental

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1 ROOF of the World Climate change and related weather/environmental impacts over the Tibetan Plateau have always drawn great interest from scientists worldwide, as they directly impact the global environment and East Asia s sustainable socioeconomic development. In recognizing such important roles of the Tibetan Plateau in the regional and global energy and water cycle, the Chinese government has recently mobilized resources for two important projects on the Tibetan Plateau and its adjacent areas. The China Meteorological Administration (CMA) and the Chinese Academy of Sciences (CAS), joined by several other related government agencies, have developed two comprehensive observational systems over the Tibetan region. Designed to fulfill the needs of meteorological operations and scientific field experiments, these systems also promote strong international cooperation and involvement in their development and application. The first project aims to establish an operational observing network, a New Integrated Observational System over the Tibetan Plateau (NIOST). As one of the key initiatives of China Japan intergovernmental cooperation, this new generation of observing network has been in development since 2005 by scientists from the Chinese Academy of Meteorological Sciences, several provincial meteorological institutes of CMA, and the University of Tokyo. NIOST focuses on China and East Asian countries weather/climate monitoring and forecasting needs, and on energy and water cycle studies. NIOST will provide routine surface and upper-air measurements of basic meteorological fields, such as temperature, pressure, wind, and humidity. Surface energy budgets from PBL towers and total precipitable water from GPS stations, as well as various satellite products, are also important additions to its datasets. The system will be in operation from The Tibetan Observation and Research Platform (TORP) is a project funded by several central and local Chinese government agencies, and focuses predominantly on research on the Tibetan Plateau s land surface, land atmosphere, and environmental processes. This project has been carried out by the Institute of Tibetan Plateau Research and other CAS institutes. TORP will provide a set of surface and near-surface hydrometeorological observations. In addition to the basic surface meteorological variables mentioned above for NIOST, soil moisture and temperature, the surface energy budget, and PBL turbulence are also measured. The complete TORP datasets will be available in Although both observing networks focus on the Tibetan Plateau, NIOST s coverage is also extended to several neighboring provinces of China to capture water-vapor downstream transport. The following two papers will describe these two projects in detail. They should provide useful information about the two valuable research platforms and datasets to the international atmospheric and environmental communities. Tibetan Observation and Research Platform Atmosphere Land Interaction over a Heterogeneous Landscape by Yaoming Ma, Shichang Kang, Liping Zhu, Baiquing Xu, Lide Tian, and Tandong Yao The Tibetan Plateau has the most prominent and complicated terrain on the globe, with an elevation averaging more than 4,000 m above mean Affiliations: Ma, Ka n g, Zh u, Xu, Ti a n, a n d Ya o Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China Corresponding Author: Yaoming Ma, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing , China ymma@itpcas.ac.cn DOI: /2008BAMS American Meteorological Society sea level (MSL). It is often called the Third Pole because its geographic significance is akin to that of Antarctica and the Arctic. The Tibetan Plateau dramatically impacts the world s environment, and especially controls climatic and environmental changes in Asia and elsewhere in the Northern Hemisphere. It therefore provides a field laboratory for studying global change. The thermal effects of the giant plateau on the atmosphere greatly influence circulations over China, East Asia, and even the entire world. The plateau absorbs a large amount of solar radiation (some of which is redistributed by cryospheric processes) and undergoes dramatic seasonal changes of sur- AMERICAN METEOROLOGICAL SOCIETY 1487

2 Table 1. The instruments and parameters measured at TORP sites. Station (site) Observation parameters Comprehensive observation and research station 20-m ABL tower (MILOS520, Vaisala Co.): Wind speed; wind direction; air temperature; humidity (height: 1.0, 2.0, 4.0, 10.0, and 20.0 m); surface temperature; soil heat flux (depth: 10 and 20 cm); air pressure; rain intensity Radiation measurement system (CNR-1, Kipp & Zonen Co.): Shortwave radiation (downward and upward); longwave radiation (downward and upward) Soil moisture and soil temperature measurement system (SMTMS): Soil moisture (Trime EZ, Imko) (depth: 10, 20, 40, 80, and 160 cm); soil temperature (Pt100, Datamark) (depth: 10, 20, 40, 80, and 160 cm) GPS radiosonde system (MW21 DigiCORA III, Vaisala): Profile of air pressure, air temperature, relative humidity, and wind speed and direction Wind Profiler and RASS (LAP3000, Vaisala): Profile of air temperature; wind speed and direction Sonic turbulent measurement system (CSAT3, Campbell) and CO /H O 2 2 flux measurement system (LI7500, Campbell): Wind speed; wind direction; air temperature; relative humidity; the characteristic length scales of surface layer; sensible heat flux; latent heat flux; CO 2 O flux; stability parameter Observational site 10-m Automatic Weather Station (AWS) (MILOS520, Vaisala): Wind speed; wind direction; air temperature; humidity (height: 1.0, 5.0, and 10.0 m); surface temperature; soil heat flux (depth: 10 and 20 cm); air pressure; rain intensity; and snow depth Radiation measurement system (CNR-1, Kipp & Zonen): Shortwave radiation (downward and upward); longwave radiation (downward and upward) Soil moisture and soil temperature measurement system (SMTMS): Soil moisture (Trime EZ, Imko) (depth: 10, 20, 40, 80, and 160 cm); soil temperature (Pt100, Datamark) (depth: 10, 20, 40, 80, and 160 cm) face heat and water fluxes. The lack of quantitative understanding of interactions between the land surface and atmosphere makes it difficult to model the complete energy and water cycles over the Tibetan Plateau and their effects on global climate change. Therefore, atmosphere land interaction studies over the Tibetan Plateau have increased in recent years. But experiments have been limited by observational parameters, and most investigations have only been done in summer and at a few locations. With support from various agencies in the People s Republic of China (see Acknowledgments ), a Tibetan Observation and Research Platform (TORP) is now focusing on the land-surface processes and environment over the plateau, with an emphasis on atmosphere land interaction. At the same time, an operational observing network, the New Integrated Observational System over the Tibetan Plateau (NIOST), has been supported by Chinese Japanese cooperation since NIOST focuses on weather monitoring and forecasting needs in East Asia and on energy and water cycle studies, and is discussed in the companion to this paper in this issue of BAMS by Xu et al. There will be 21 comprehensive observation and research stations and 16 additional observational sites in the TORP. Of these, 11 comprehensive observation and research stations and 10 observational sites will be configured for the study of atmosphere land interaction (see Fig. 1) by the end of Each comprehensive observation and research station will include 20-m atmospheric boundary layer (ABL) towers (wind speed, wind direction, air temperature, and humidity at five levels), a four-component radiation measurement system, a five-level soil moisture and soil temperature measurement system (SMTMS), a GPS radiosonde system, a Wind Profiler and Radio Acoustic Sounding System (RASS), a sonic turbulent measurement system and CO 2 O flux measurement system, a precipitation monitoring system, 1488

3 and a soil heat flux measurement system. Each additional observational site includes a 10-m automatic weather station (AWS) (wind speed, wind direction, air temperature, and humidity at three levels), the radiation measurement system, the SMTMS, the precipitation and snow depth system, and the soil heat flux system (see Table 1). They will all monitor the atmosphere (from the stratosphere to the surface layer) as well as ground-surface processes. Three comprehensive observation and research stations (Mt. Qomolangma Mt. Everest, Nam Co, and Linzhi) were established by the Institute Fig.1. The Tibetan Observation and Research Platform (TORP) for the study of Tibetan Plateau Research of atmosphere land interaction on the Tibetan Plateau. ( = comprehensive observation and research station; = observational site; = mesoscale (ITP) of the Chinese Academy experimental area of the GAME/Tibet and the CAMP/Tibet) of Sciences (CAS) in August The comprehensive observation and research stations of Haibei, Golmud, Mushitageta will be established by the end of Lhasa, and Mt. Gongga were established by other in- Shuanghu station and Mt. Tanggula station will be stitutes of CAS around the beginning of All the established by ITP/CAS by the end of All 10 established stations are working well now and have observational sites are just in the planning stage now yielded a large amount of data. Ali station and Mt. and will be set up by the end of One of the important pa r ts of TOR P is t he Mesoscale mesoscale mesoscale monitoring network (see Figs. 1 and 2). It worked successfully during the Global Energy and Water Cycle Experiment (GEWEX), the Asian Monsoon Experiment on the Tibetan Plateau (GAME/Tibet, ) and the Coordinated Enhanced Observing Period (CEOP) Asia Australia Monsoon Project on the Tibetan Plateau (CAMP/Tibet, ). This monitoring network was established at the beginning of 1998 during GAME/TiFig.2. Site layout during GAME/Tibet and CAMP/Tibet. AMERICAN METEOROLOGICAL SOCIETY 1489

4 bet, and more instruments were set up during CAMP/ Tibet and will be continued in TORP (see Fig. 2 and Table 2). It covered a km area ( N, E), and many kinds of instruments have been deployed in the network (see Fig. 1, Fig. 2, and Table 2). Large amounts of data were collected during GAME/Tibet and CAMP/Tibet, which was the best dataset to date for Tibetan Plateau hydrometeorology. Using the data, substantial research progress has been made in land and atmosphere processes, remote sensing, and land data assimilation. It is best to extend the observations as long as possible for the study of atmosphere land interaction and climatic change over the Tibetan Plateau and surrounding areas. Therefore, all the instruments in GAME/Tibet and CAMP/Tibet will be continued for long-term observations in TORP. The data collected in the TORP will be archived by the TORP data center in the ITP. The archived data will be available to the scientific community all Table 2. The instruments and parameters measured in the TORP mesoscale network. Site Observation item Amdo PBL (ABL) tower (MILOS500, Vaisala): Wind speed (Aerobane FF-11, Ogasawara) (height: 1.9, 6.0, and 14.1 m); wind direction (Aerobane FF-11, Ogasawara) (height: 14.1 m); air temperature (HMP35D-Pt100, Vaisala) and humidity (Electric Capacitance, Ibid) (height: 1.55, 5.65, and m), surface temperature(mf-81, Optex); soil heat flux (MF-81, EKO) (depth: 10 and 20 cm); air pressure (DPA21, Vaisala); rain intensity (RG-13, Vaisala) Radiation: Downward and upward shortwave radiation (CM21, Kipp & Zonen); downward and upward longwave radiation (Precision Infrared Radiometer, Eppley) Automatic Weather Station (AWS) (D110, MS3608) Wind speed and wind direction at 6.0 m (WS-942, Ogasawara); air temperature and humidity at 1.5 m (HMP35A, Vaisala); surface temperature (HR1-FL, Chino); soil temperature at -20 cm (Pt-100, Vaisala); solar radiation (S-100, EKO); air pressure (PTB100, Vaisala); rain intensity (RG-13, Vaisala) Automatic Weather Station (AWS) (D105, MS3478, BJ, ANNI) Wind speed (WS-D32, Komatsu) ( height: 10, 5, and 1.0 m); wind direction at 10 m (WS-D32, Komatsu); air temperature (TS-801, Okazaki) and humidity (HMP- 45D, Vaisala) (height: 9.0 and 1.0 m); downward and upward shortwave radiation (CM21, Kipp & Zonen); downward and upward longwave radiation (Precision Infrared Radiometer, Eppley); air pressure (PTB220C, Vaisala); surface temperature (IRt/C 1X-T50F, Exergen); snow depth (SR-50, Campbell); precipitation (NOAH- II, ETI); soil heat flux (MF-81, EKO) (depth: 10 and 20 cm) Soil moisture and soil temperature system (D105, D110, Amdo, BJ, ANNI, MS3608, MS3637) Soil temperature (Pt100, Datamark) (depth: 4, 20, 60, 80, 100, 130, 160, 200, and 279 cm); soil moisture (Trime EZ, Imko) (depth: 4, 20, 60, 100, 160, and 258 cm) Turbulent measurement (BJ) Sonic turbulent measurement system (DA-600, Kaijo Denki) and CO 2 O flux measurement system (LI7500, Campbell): wind speed; wind direction; air temperature; relative humidity; the characteristic length scales of surface layer; sensible heat flux; latent heat flux; CO 2 O flux; stability parameter Wind Profiler and RASS (LAP3000, Vaisala) (BJ) Profile of air temperature, and wind speed and direction 1490

5 over the world within two years after measurements are taken. The complete TORP datasets will be available in Scientists can submit a proposal to the data center to apply for use of the data, and they can download the data from the center Web site. The data collected in TORP could be used for analysis of land and atmospheric processes, model/ scheme development, model calibration, validation, and other tasks. Results from the process studies and parameterization can be used as input to atmospheric models, or for remote sensing and data assimilation studies. The results from the remote sensing and data assimilation can also be used as input for the atmospheric models. Using the atmospheric models, remote sensing, and data assimilation methodologies, the point or local-scale process studies and parameterizations can be scaled up to the Tibetan Plateau scale. The plateau scale results can also be validated by the stations and sites data (see Fig. 3). In this way, we believe TORP can contribute to the study of impacts of the Tibetan Plateau on the Asian Monsoon system and climatic change over China, East Asia, and the entire globe. ACKNOWLEDGMENTS. This paper was written under the auspices of the Chinese National Key Programme for Developing Basic Sciences (2005CB422003) and the National Natural Science Foundation of China ( ). TORP is supported by the Chinese Academy of Sciences, the Ministries of Science and Technology and of Education, and by the State Forest Administration of the People s Republic of China, the China Meteorological Administration, and the Tibetan Autonomous Region of China. The authors thank all the colleagues in these entities and in the Institute of Tibetan Plateau Research and other institutes for their hard work in TORP. FOR FURTHER READING Ma, Y., and O. Tsukamoto, 2002: Combining Satellite Remote Sensing with Field Observations for Land Surface Heat Fluxes over Inhomogeneous Landscape. China Meteorological Press, 172 pp., and Coauthors, 2003: Regionalization of surface fluxes over heterogeneous landscape of Tibetan Plateau by using satellite remote sensing data. J. Meteor. Soc. Japan, 81, Fig.3. The upscaling diagram for the study of atmosphere land interaction on the Tibetan Plateau., and Coauthors, 2005: Diurnal and inter-monthly variation of land surface heat fluxes over the central Tibetan Plateau area. Theor. Appl. Climatol., 80, , L. Zhong, Z. Su, H. Ishikawa, M. Menenti, and T. Koike, 2006: Determination of regional distributions and seasonal variations of land surface heat fluxes from Landsat-7 Enhanced Thematic Mapper data over the central Tibetan Plateau area. J. Geophys. Res., 111, D10305, doi: /2005jd Oku, Y., H. Ishikawa, S. Haginoya and Y. Ma, 2006: Recent trends in land surface temperature on the Tibetan Plateau. J. Climate, 19, Tanaka, K., H. Ishikawa, I. Tamagawa, and Y. Ma, 2001: Surface energy budget at Amdo on Tibetan Plateau using GAME/Tibet IOP 98 data. J. Meteor. Soc. Japan, 79, Xu, X., and Coauthors, 2002: A comprehensive physical pattern of land air dynamic and thermal structure on the Qinghai Xizang Plateau. Sci. China, Ser. D, 32, , and Coauthors, 2008: A New Integrated Observational System over the Tibetan Plateau (NIOST). Bull. Amer. Meteor. Soc., 89, Yanai, M., C. Y. Li, and Z. Song, 1992: Seasonal heating of the Tibetan Plateau and its effects on the evolution of the Asian summer monsoon. J. Meteor. Soc. Japan, 70, Yang, K., T. Koike, and D. Yang, 2003: Surface flux parameterization in the Tibetan Plateau. Bound.-Layer Meteor., 106, ,, H. Fujii, T. Tamura, X. Xu, L. Bian, and M. Zhou, 2004: The daytime evolution of the atmospheric boundary layer and convection over the Tibetan Plateau: Observations and simulations. J. Meteor. Soc. Japan, 82, ,, P. Stackhouse, C. Mikovitz, and S. J. Cox, 2006: An assessment of satellite surface radiation products for highlands with Tibet instrumental data. Geophys. Res. Lett., 33, L22403, doi: /2006gl AMERICAN METEOROLOGICAL SOCIETY 1491

6 , T. Watanabe, T. Koike, X. Li, H. Fujii K. Tamagawa, Y. Ma, and H. Ishikawa, 2007: Auto-calibration system developed to assimilate AMSR-E data into a land surface model for estimating soil moisture and the surface energy budget. J. Meteor. Soc. Japan, 85A, Ye, D., 1981: Some characteristics of the summer circulation over the Qinghai-Xizang (Tibet) Plateau and its neighborhood. Bull. Amer. Meteor. Soc., 62, , and Y. Gao, 1979: The Meteorology of the Qinghai- Xizang (Tibet) Plateau (in Chinese). Science Press, 278 pp., and G. Wu, 1998: The role of the heat source of the Tibetan Plateau in the general circulation. Meteor. Atmos. Phys., 67, Zhang, Q., B. Zhu, F. Zhu, D. Wang, G. Sun, J. Lu, Y. Peng, and Y. Wang, 1988: Advances in the Qinghai- Xizang Plateau Meteorology: The Qinghai-Xizang Plateau Meteorological Experiment (1979) and Research (in Chinese). Science Press, 268 pp 1492