Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data
Abstract An analysis is made of the adjustments needed to produce three homogeneous data sets, namely the 1961–1990 mean temperatures in Finland, the North Atlantic Climatolological Dataset (NACD) temperature and precipitation series (1890–1990), and the Finnish daily mean maximum and minimum temper...
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crwiley:10.1002/joc.616 2024-06-02T08:11:40+00:00 Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data Tuomenvirta, H. 2001 http://dx.doi.org/10.1002/joc.616 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjoc.616 https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/joc.616 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor International Journal of Climatology volume 21, issue 4, page 495-506 ISSN 0899-8418 1097-0088 journal-article 2001 crwiley https://doi.org/10.1002/joc.616 2024-05-03T10:52:06Z Abstract An analysis is made of the adjustments needed to produce three homogeneous data sets, namely the 1961–1990 mean temperatures in Finland, the North Atlantic Climatolological Dataset (NACD) temperature and precipitation series (1890–1990), and the Finnish daily mean maximum and minimum temperature series (1910–1995), as well as the reasons for making such adjustments. The adjustments in the annual (seasonal) mean temperatures are up to ±1°C (±2°C), and annual precipitation adjustments can be ±40%. In Finland, the homogeneity breaks in the normal period temperatures and in the long‐term daily mean maximum and minimum temperatures appear to be random, and thus, do not bias averages based on large numbers of stations. However, both the temperature and precipitation series of the NACD would have been statistically significantly biased without adjustments. Station relocations appear to be the most common cause of homogeneity breaks in the temperature series. In the NACD, the adjustments resulting from relocations are statistically significant and reflect changes to colder observing sites. Also, changes in the formula used for the calculation of mean temperatures and urbanization both cause systematic biases in the data. The installation of improved precipitation gauges has been systematic in the NACD; thus, the original series need to be adjusted upwards in the early years. The applied adjustments are of the same order of magnitude as the observed long‐term trends, which stresses the importance of the testing and adjusting of long‐term series before analysis of climatic changes. In order to monitor climatic changes in a reliable manner, the observing network should be designed to withstand the common discontinuities (e.g. relocations, observer and environment changes etc.) in observation series, because the number of homogeneity breaks appears to be roughly constant in time. Moreover, the introduction of new technology may cause systematic changes in the observations, and comprehensive comparison measurements ... Article in Journal/Newspaper North Atlantic Wiley Online Library International Journal of Climatology 21 4 495 506 |
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English |
description |
Abstract An analysis is made of the adjustments needed to produce three homogeneous data sets, namely the 1961–1990 mean temperatures in Finland, the North Atlantic Climatolological Dataset (NACD) temperature and precipitation series (1890–1990), and the Finnish daily mean maximum and minimum temperature series (1910–1995), as well as the reasons for making such adjustments. The adjustments in the annual (seasonal) mean temperatures are up to ±1°C (±2°C), and annual precipitation adjustments can be ±40%. In Finland, the homogeneity breaks in the normal period temperatures and in the long‐term daily mean maximum and minimum temperatures appear to be random, and thus, do not bias averages based on large numbers of stations. However, both the temperature and precipitation series of the NACD would have been statistically significantly biased without adjustments. Station relocations appear to be the most common cause of homogeneity breaks in the temperature series. In the NACD, the adjustments resulting from relocations are statistically significant and reflect changes to colder observing sites. Also, changes in the formula used for the calculation of mean temperatures and urbanization both cause systematic biases in the data. The installation of improved precipitation gauges has been systematic in the NACD; thus, the original series need to be adjusted upwards in the early years. The applied adjustments are of the same order of magnitude as the observed long‐term trends, which stresses the importance of the testing and adjusting of long‐term series before analysis of climatic changes. In order to monitor climatic changes in a reliable manner, the observing network should be designed to withstand the common discontinuities (e.g. relocations, observer and environment changes etc.) in observation series, because the number of homogeneity breaks appears to be roughly constant in time. Moreover, the introduction of new technology may cause systematic changes in the observations, and comprehensive comparison measurements ... |
format |
Article in Journal/Newspaper |
author |
Tuomenvirta, H. |
spellingShingle |
Tuomenvirta, H. Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
author_facet |
Tuomenvirta, H. |
author_sort |
Tuomenvirta, H. |
title |
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
title_short |
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
title_full |
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
title_fullStr |
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
title_full_unstemmed |
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data |
title_sort |
homogeneity adjustments of temperature and precipitation series—finnish and nordic data |
publisher |
Wiley |
publishDate |
2001 |
url |
http://dx.doi.org/10.1002/joc.616 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjoc.616 https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/joc.616 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
International Journal of Climatology volume 21, issue 4, page 495-506 ISSN 0899-8418 1097-0088 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/joc.616 |
container_title |
International Journal of Climatology |
container_volume |
21 |
container_issue |
4 |
container_start_page |
495 |
op_container_end_page |
506 |
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1800757887906086912 |