Foreshore Authority

• Main Authors: Daily Observations At Green Harbour, Per Øyvind Nordli, Jack Kohler, Per Øyvind, Nordli Eirik Førland
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: The early 20th century warming Daily observatio; Svalbard; ACIA; Green Harbour
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.600.3802; http://met.no/Forskning/Publikasjoner/Publikasjoner_2003/filestore/klima-03-12.pdf

1912-September 1930), has thus far only been available digitally in the form of monthly mean values. ACIA (Artic Climate Impact Assessment) funded the digitisation of three main daily observations, permitting quality control of the series that were impossible with the monthly means only. In addition, measurements from a German-Austrian scientific overwintering expedition (1911-1912) have been digitised. Analysis of the Green Harbour data shows that in some periods, particularly in the early part of the series, the monthly data have not been of top quality; this resulted in a few corrections to mean monthly values. However, correcting the original series does not change the annual or seasonal trends, and the steep rise in temperature at the beginning of the series (1911-1920), known in high northern latitudes as the early 20th century warming, is maintained. Two-thirds of this temperature increase could be explained at Green Harbour by a increase in winter (December-March) cloud cover. The long-term series valid for the Svalbard Airport was revised and a new series established (Sep. 1911 – Nov. 2003) with only minor changes compared to the previous series. A positive trend for the spring temperature (March-May) is highly significant, whereas the trends in the other seasons are not significant at the 5 % level. However, the positive trend of the annual series is very close to being significant at this level (p = 5.2 %).