Trends of Maximum and Minimum Temperatures in Northern South America

Ramon A. Quintana-Gomez Department of Earth Sciences, Universidad de los Llanos Ezequiel Zamora, Barinas, Estado Barinas, Venezuela

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Abstract

This paper presents the results of testing the homogeneity of the basic data used in this study, that is, the mean monthly maximum and minimum temperature (as derived from daily observations) of several long-term climatological stations of Venezuela and Colombia, and an evaluation of the fluctuations and deviations from long-term means of such parameters, as well as of the diurnal temperature ranges (DTR) during the 73-yr period, 1918–90. The 14 longest-term climatological stations in Venezuela and Colombia with available metadata and the most consistent temperature records were used. Homogeneity tests were done by application of the Alexandersson’s Test. Eleven stations (the ones with less inhomogeneities) were finally left for partial data adjustments of their records when needed (only a few of them), following the technique developed by Easterling and Peterson. Then, the temperature trends and deviations from long-term averages (1918–90) were determined. The most remarkable feature of the analysis is a relative and sustained increase of the minimum temperature series and a DTR decrease during the last 25 yr of the period at a significant rate in most of the station records.

Corresponding author address: Dr. Ramon A. Quintana-Gomez, Universidad Nacional Experimental de los Llanos Ezequiel Zamora, UNELLEZ, Barinas, 5201 Edo. Barinas, Venezuela. E-mail: rquint@saman.unellez.edu.ve

Abstract

This paper presents the results of testing the homogeneity of the basic data used in this study, that is, the mean monthly maximum and minimum temperature (as derived from daily observations) of several long-term climatological stations of Venezuela and Colombia, and an evaluation of the fluctuations and deviations from long-term means of such parameters, as well as of the diurnal temperature ranges (DTR) during the 73-yr period, 1918–90. The 14 longest-term climatological stations in Venezuela and Colombia with available metadata and the most consistent temperature records were used. Homogeneity tests were done by application of the Alexandersson’s Test. Eleven stations (the ones with less inhomogeneities) were finally left for partial data adjustments of their records when needed (only a few of them), following the technique developed by Easterling and Peterson. Then, the temperature trends and deviations from long-term averages (1918–90) were determined. The most remarkable feature of the analysis is a relative and sustained increase of the minimum temperature series and a DTR decrease during the last 25 yr of the period at a significant rate in most of the station records.

Corresponding author address: Dr. Ramon A. Quintana-Gomez, Universidad Nacional Experimental de los Llanos Ezequiel Zamora, UNELLEZ, Barinas, 5201 Edo. Barinas, Venezuela. E-mail: rquint@saman.unellez.edu.ve

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  • Alexandersson, H., 1986: A homogeneity test applied to precipitation data. J. Climatol.,6, 661–675.

  • ——, 1995: Homogeneity testing, multiple breaks and trends. Extended Abstracts, Sixth Int. Meeting on Statistical Climatology, Galway, Ireland, Steering Committee for International Meetings on Statistical Climatology 439–441.

  • Easterling, D. R., and T. C. Peterson, 1992: Techniques for detecting and adjusting for artificial discontinuities in climatological time series: A review. Preprints, Fifth Int. Meeting on Statistical Climatology, Toronto, ON, Canada, Steering Committee for International Meetings on Statistical Climatology, J28–J32.

  • ——, and ——, 1995: A new method for detecting undocumented discontinuities in climatological time series. lnt. J. Climatol.,15, 369–377.

  • ——, and ——, and T. R. Karl, 1996: On the development and use of homogenized climate datasets. J. Climate,9, 1429–1434.

  • ——, and Coauthors, 1997: Maximum and minimum temperature trends for the globe. Science,277, 364–367.

  • Great Britain Meteorological Office, 1957: Reséau Mondial of the years 1910 through 1934. 410 pp.

  • HIMAT, 1993: Promedios de temperaturas maxímas, mínimas, medias mensuales de dieciocho estaciones meteorológicas de larga data, 40 pp.

  • IPCC, 1990: Climate Change: The IPCC Scientific Assessment. Cambridge University Press, 362 pp.

  • ——, 1992: Climate Change 1992: The Supplementary Report to the IPCC Scientific Assessment. Cambridge University Press, 200 pp.

  • Jones, P. D., 1988: Hemispheric surface air temperature variation: Recent trends and an update to 1987. J. Climate,3, 243–252.

  • ——, P. M. Kelly, T. M. Wigley, S. C. B. Raper, R. S. Bradley, and H. F. Diaz, 1986a: Northern Hemisphere surface air temperature variations, 1851–1984. J. Climate Appl. Meteor.,25, 161–179.

  • ——, ——, ——, ——, ——, and ——, 1986b: Southern Hemisphere air temperature variations, 1851–1984. J. Climate Appl. Meteor.,25, 1213–1230.

  • ——, P. Ya. Goisman, M. Coughlan, N. Plumber, W. C. Wang, and T. R. Karl, 1990: Assessment of urbanization effects in time series of surface air temperature over land. Nature,347, 169–172.

  • Karl, T. R. and P. D. Jones, 1990: Reply. Bull. Amer. Meteor. Soc.,71, 572–574.

  • ——, G. Kukla, and J. Gavin, 1984: Decreasing diurnal temperature range in the United States and Canada from 1941 to 1980. J. Climate Appl. Meteor.,23, 1489–1504.

  • ——, C. W. Williams, Jr., P. J. Young, and W. M. Wendland, 1986: A model to estimate the time of observation bias associated with monrhly mean maximum, minimum and mean temperatures for the United States. J. Climate Appl. Meteor.,25, 145–160.

  • ——, R. G. Quayle, and P. Ya. Groisman, 1993a: Detecting climate variations and change: New challenges for observing and data management systems. J. Climate,6, 1481–1494.

  • ——, and Coauthors, 1993b: A new perspective on recent global warming: Assymetric trends of daily maximum and minimum temperatures. Bull. Amer. Meteor. Soc.,74 1007–1023.

  • Keiser, D. T., 1994: The Alexandersson test for homogeneity of temperature data: A case study for the northern Great Plains. M.S. thesis, Dept. of Meteorology, Texas A&M University, 116 pp.

  • Peterson, T. C., and D. R. Easterling, 1994: Creation of homogeneous composite climatological reference series. Int. J. Climatol.,14, 671–679.

  • Quintana-Gomez, R. A., 1986: Probabilidad de ocurrencia de periodos secos cortos en la estacion lluviosa de Llanos Altos Occidentales de Venezuela. Rev. Unellez Ciencia Technol.,4, 23–32.

  • ——, 1991: Análisis meteorológico de los años de baja pluviosidad 1984 y 1985 y evaluacíon de ciclos de occurrencia de años secos. Rev. Unellez Ciencia Technol.,9, 41–57.

  • ——, 1998: Changes in evaporation patterns detected in northernmost South America. Homogeneity testing. Preprints, Seventh Int. Meeting on Statistical Climatology, Whistler, BC, Canada, Steering Committee for International Meetings on Statistical Climatology, 97.

  • SMFAV, 1993: Promedios mensuales de temperaturas máximas, mínimas y medias y de precipitación de las nueve estaciones climatológicas Venezolanas de más largo registro. Imprenta FAV, Maracay, Venezuela, 36 pp.

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