Weather types and their frequencies over Central Asia – an ERA-Interim based analysis of monthly climate variability and change for the boreal cold season

Sebastian Schmidt*, Lars Gerlitz

Helmholzzentrum Potsdam – German Research Centre for Geosciences, Section Hydrology, Germany

*Corresponding author:

Research paper


Climate research in Central Asia is usually based on the analysis of meteorological observations. However, data scarcity in mountain regions causes uncertainties and, thus, the magnitude of climate change and variability in Central Asia is still under debate. Furthermore, the investigation of observations does only allow an assessment of the near surface climate. Since the meteorological conditions in the upper troposphere are generally unknown, the atmospheric mechanisms leading to observed climate changes remain unexamined. Here, the authors present a study of climate change and variability in Central Asia based on the ERA-Interim reanalysis, which provides gridded data-sets of various meteorological parameters for 60 atmospheric levels. In order to investigate the climatic conditions during the boreal cold season, the authors apply an objective weather type classification to 500hPa geopotential height fields. The results show that warm and wet conditions in Central Asia are associated with an anticyclonic anomaly over South Asia or a southward shift of the westerly jet stream. Dry conditions are accompanied by a cyclonic anomaly over South Asia. The authors show that the WT composition strongly affects the monthly and seasonal temperature and precipitation characteristics and that prevailing climatic trends are partially triggered by changing WT frequencies.About 50% of the seasonal temperature trend and 60% of the trend in March can be explained by WT frequency changes. While the observed seasonal precipitation trendscannot be explained by WT frequency changes, a positive trend in November seems to be accompanied by a decreasing frequency of high pressure over Central Asia.

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How to cite: Schmidt, S., & Gerlitz, L. (2019). Weather types and their frequencies over Central Asia –an ERA-Interim based analysis of monthly climate variability and change for the boreal cold season. Central Asian Journal of Water Research, 5(2), 64–99.


  1. Apel, H., Abdykerimova, Z., Agalhanova, M., Baimaganbetov, A., Gavrilenko, N., Gerlitz, L., Kalashnikova, O., Unger-Shayesteh, Katy., Vorogushyn, S., and Gafurov, A., 2018. Statistical forecast of seasonal discharge in Central Asia for water resources management: development of a generic linear modelling tool for operational use, Hydrology and Earth System Science, Vol. 22, pp. 2225-2254.
  2. Bao, X., and F. Zhang, 2012. Evaluation of NCEP–CFSR, NCEP–NCAR, ERA-Interim, and ERA-40 Reanalysis Datasets against Independent Sounding Observations over the Tibetan Plateau, Journal of climate, Vol. 26, pp. 206–214. Available at:
  3. Barlow, M., Cullen, H. and Lyon, B., 2002. Drought in central and southwest Asia: La Niña, the warm pool, and Indian Ocean precipitation, Journal of climate,  Vol. 15, No. 7, pp. 697-700.
  4. Barlow, M. A. and Tippett, M. K., 2008. Variability and Predictability of Central Asia River Flows: Antecedent Winter Precipitation and Large-Scale Teleconnections, Journal of Hydrometeorology, Vol. 19, No. 9, pp. 1334-1349.
  5. Barlow, M. and Hoell, A., 2015. Drought in the Middle East and Central-Southwest Asia During Winter 2013/14, Bulletin of the American Meteorological Society, Vol. 96, No. 7, pp. 71-76.
  6. Barlow, M., Zaitchik, B., Paz, S., Black, E., Evans, J. and Hoell, A., 2016. A review of drought in the Middle East and southwest Asia, Journal of climate, Vol. 29, No. 23, pp. 8547-8574.
  7. Böhner, J., 2006. General climatic controls and topoclimatic variations in Central and High Asia. Boreas, Vol. 782, No. 35, pp. 279-295.
  8. Bothe, O., Klaus, F. and Xiuhua Z., 2011. Precipitation climate of Central Asia and the large-scale atmospheric circulation, Theoretical and applied climatology, Vol. 108, pp. 345-354.
  9. Bradley, P. S., Fayyad, U. M. and Reina, C., 1998. Scaling Clustering Algorithms to Large Databases. In: KDD 98, pp. 9-15.
  10. Cahalan, R. F., 1983. EOF spectral estimation in climate analysis. Second International Meeting on Statistical Climatology, pp. 1-4.
  11. Chanysheva, S. G., Subbotina, O. I., Petrov, U. V., Egamberdiyev, K. T., Aizenshtat, B. A. and Leukhina, G. N., 1995. Variability of the Central Asian Climate. Central Asian Hydrometeorological Research Institute, Tashkent. [in Russian]
  12. Chen, F., Wang, J., Jin, L., Zhang, Q., Li, J. and Chen, J., 2009. Rapid warming in mid-latitude central Asia       for the past 100 years. Frontiers of Earth Science in China, pp. 3-42.
  13. Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy,   S., B., Hersbach, H., Hólm, E. V., Isaksen, L., Kållberg, M., Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J.-N. and Vitart, F., 2011. The ERA‐Interim reanalysis: Configuration and performance of the data assimilation system, Quarterly Journal of the royal meteorological society, Vol. 137, No. 656, pp. 553-597.
  14. de Pauw, B., 2007. Principal biomes of Central Asia. In: Lal R., Sulaimonov, M., Stewart, B. A., Hansen, D. O., Doraiswamy, P., In: Climate change and terrestrial carbon sequestration in Central Asia, Pp. 137-146. Taylor and Francis, New York, USA.
  15. Dimri, A. P., 2013. Interannual variability of Indian winter monsoon over the Western Himalayas, Global and planetary change, Vol. 106, pp. 39-50.
  16. Dukhovny, V., 2010. Present problems of irrigated agriculture in Aral Sea basin and future decisions. Oral Presentation at the International Scientific Symposium “Water in Central Asia”, Tashkent, 24-26 November 2010. Available at: (Accessed August 10, 2012).
  17. Dukhovny, V. A. and de Schutter, J. 2011. Water in Central Asia: past, present, future. CRC Press/Balkema.
  18. ECMWF, 2016. ECMWF. Forecast. Datasets. ERA-INTERIM. (Accessed November 28, 2016).
  19. Forgy, E. W., 1965. Cluster analysis of multivariate data: efficiency versus interpretability of classifications, Biometrics Vol. 21, pp. 768-769.
  20. Gerlitz, L., O. Conrad, A. Thomas, and J. Böhner, 2014. Warming patterns over the Tibetan Plateau and adjacent lowlands derived from elevation- and bias‑corrected ERA-Interim data, Climate research, Vol. 58, pp. 235–246, Available at:
  21. Gerlitz, L., Conrad, O. and Böhner, J., 2015. Large-scale atmospheric forcing and topographic    modification of precipitation rates over High Asia-a neural-network-based approach, Earth system dynamics, Vol. 6, No. 1, p. 61.
  22. Gerlitz, L., Vorogushyn, S., Apel, H., Gafurov, A., Unger-Shayesteh, K. and Merz, B., 2016. A statistically         based seasonal precipitation forecast model with automatic predictor selection and its application to central and south Asia, Hydrology and Earth system sciences, Vol. 20, No. 11, pp. 4605-4623.
  23. Gerlitz, L., Steirou, E., Schneider, C., Moron, V., Vorogushyn, S. and Merz, B., 2018. Variability of the cold season climate in Central Asia – Part I: Weather types and their tropical and extratropical drivers, Journal of climate, Vol. 31, pp. 7185–7207, Available at:
  24. Giese, E. and Mossig, I., 2004. Klimawandel in Zentralasien (Climate Change in Central Asia). Zentrum für Internationale Entwicklungs- und Umweltforschung: Discussion papers 17, 70, Giessen. [in German]
  25. Giorgi, F., 2006. Climate change hot-spots, Geophysical research letters, Vol. 33, L08707.
  26. Golian, S., Mazdiyasni, O. and AghaKouchak, A., 2015. Trends in meteorological and agricultural droughts      in Iran, Theoretical and applied climatology, Vol. 119, No. 3-4, pp. 679-688.
  27. Hoell, A., Funk, C. and Barlow, M., 2014. The regional forcing of Northern hemisphere drought during recent warm tropical west Pacific Ocean La Niña events, Climate dynamics, Vol. 42, No. 11-12, pp. 3289-3311.
  28. Huth, R., Beck, C., Philipp, A., Demuzere, M., Ustrnul, Z., Cahynová, M., Kyselý, J. and Tveito, O.E., 2008. Classifications of atmospheric circulation patterns, Annals of the New York Academy of Sciences, Vol. 1146, pp. 105-152.
  29. Intergovernmental Panel on Climate Change, ed., 2014. Climate Change 2013 – The Physical Science Basis: Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge. Available at: (Accessed February 20, 2018).
  30. Jacobeit, J., 2010. Classifications in climate research, Physics and chemistry of the Earth. Parts A/B/C, Vo. 35, No. 9-12, pp. 411-421.
  31. Käsmacher, O., and C. Schneider, 2011. An Objective Circulation Pattern Classification for the Region of Svalbard. Geografiska Annaler: Series A, Physical Geography, Vol. 93, pp. 259–271. Available at:
  32. Lloyd, S., 1982. Least squares quantization in PCM, IEEE transactions on information theory, Vol. 28, No. 2, pp. 129-137.
  33. Maćkiewicz, A. and Ratajczak, W., 1993. Principal components analysis (PCA), Computers and geosciences, Vol. 19, pp. 303-342.
  34. MacQueen, J., 1967. Some methods for classification and analysis of multivariate observations. In: Proceedings of the fifth Berkeley symposium on mathematical statistics and probability, Vol. 1, No. 14, pp. 281-297.
  35. Martyn, D., 1992. Climates of the world. developments in atmospheric science. Elsevier, Amsterdam [u.a.], Netherlands; PWN, Warszawa, Poland.
  36. Mariotti, A., 2007. How ENSO impacts precipitation in southwest central Asia, Geophysical research letters, Vol. 34, No. 16.
  37. Michelangeli, P. A., Vautard, R. and Legras, B., 1995. Weather regimes: Recurrence and quasi stationarity, Journal of the atmospheric sciences, Vol. 52, No. 8, pp. 1237-1256.
  38. Mirzabaev, A., 2013. Impact of weather variability and climate change on agricultural revenues in Central Asia, Quarterly journal of international agriculture, Vol. 52, No. 3, pp. 179-194.
  39. Natural Earth, 2019. Natural Earth. Downloads. Available at: (Accessed January 14, 2019).
  40. QGIS, 2019. Laden Sie QGIS für Ihre Plattform herunter. Available at: (Accessed January 14, 2019).
  41. Rasmusson, E. M., Arkin, P. A., Chen, W. Y. and Jalickee, J. B. 1981. Biennial variations in surface temperature over the United States as revealed by singular decomposition, Monthly weather review, Vol. 109, No. 3, pp. 587-598.
  42. Roller, C. D., Qian, J. H., Agel, L., Barlow, M. and Moron, V., 2016. Winter weather regimes in the northeast United States, Journal of climate, Vol. 29, No. 8, pp. 2963-2980.
  43. Schiemann, R. D., Lüthi, P. L. and Vidale, Schär C., 2008. The precipitation climate of Central Asia – intercomparison of observational and numerical data sources in a remote semiarid region, International journal of climatology, Vol. 28, pp. 3-24.
  44. Schiemann, R., Lüthi, D. and Schär, C., 2009. Seasonality and interannual variability of the westerly jet in the Tibetan Plateau region, Journal of climate, Vol. 22, No. 11, pp. 2940-2957.
  45. Sommer, R., Glazirinaa, M., Yuldashev, T. , Otarov, A., Ibraeva, M., Martynova, L., Bekenov, M., Kholov, B., Ibragimov, N., Kobilov, R., Karaev, S., Sultonov, M., Khasanova, F., Esanbekov, M., Mavlyanov, D., Isaev, S., Abdurahimov, S., Ikramov, R., Shezdyukova, L. and de Pauw E., 2013. Impact of climate change on wheat productivity in Central Asia. Agriculture, Ecosystems and Environment, Vol. 178, pp. 78-99.
  46. SRTM, 2019. SRTM Data. Available at: (Accessed January 14 2019).
  47. Syed, F. S., Giorgi, F., Pal, J. S. and King, M. P., 2006. Effect of remote forcings on the winter precipitation         of central southwest Asia part 1: Theoretical and Applied Climatology, Vol. 108, pp. 147-160.
  48. Syed, F. S., Giorgi, F., Pal, J. S. and Keay, K., 2010. Regional climate model simulation of winter climate over Central-Southwest Asia, with emphasis on NAO and ENSO effects, International journal of climatology, Vol. 30, No. 2, pp. 220-235.
  49. Trigo, R. M., Gouveia, C. M. and Barriopedro, D., 2010. The intense 2007-2009 drought in the Fertile            Crescent: Impacts and associated atmospheric circulation, Agricultural and forest meteorology, Vol. 150, No. 9, pp. 1245-1257.
  50. TUM (Technical University of Munich), 2018. Clusteranalyse (e-learning in German). Available at: (Accessed January 20, 2020).
  51. Unger-Shayesteh, K., Vorogushyn, S., Farinotti, D., Gafurov, A., Duethmann, D., Mandychev, A. and Merz, B., 2013. What do we know about past changes in the water cycle of Central Asian headwaters? A review, Global planetary change, Vol. 110, pp. 4-25.
  52. Wang, A. and Zeng, X., 2012. Evaluation of multireanalysis products with in situ observations over the Tibetan Plateau, Journal of geophysical research: Atmospheres, Vol. 117 (D5).
  53. World Bank, 2018. The World Bank Open Data. Population, total. Available at: (Accessed June 02, 2018).
  54. Yin, Z. Y., Wang, H., Liu, X., 2014. A comparative study on precipitation climatology and interannual variability in the lower midlatitude East Asia and Central Asia, Journal of climate, Vol. 27, No. 20, pp. 7830-7848.

climate change, climate variability, precipitation, temperature, weather types

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