NARP Station Catalogue (monthly values)

1. NARP Station Catalogue (monthly values) NARP WMO DMS Desimal degrees element number Station name Init number number Lat./Long. Latitude Longitude 101 111 112 121 122 401 601 602 701 801 Faroe Islands Torshavn TORS 06011 6011 62 01 N 06 46 W 62.0167 -6.7667 1890-1999 1873-1999 1873-1999 1873-1999 1873-1999 1880-1999 1890-1999 1890-1999 1939-1999 1890-1999 Strond Kr.st. STRO 33054 - 62 16 N 06 35 W 62.2667 -6.5833 n.a n.a n.a n.a n.a n.a 1961-1999 1961-1999 n.a n.a Greenland Upernavik UPER 04210 4210 72 47 N 56 10 W 72.7833 -56.1667 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1997 1949-1986 1938-1981 1890-1981 Jakobshavn JAKO 04216 4216 69.2167 -51.0667 1890-1991 n.a., ref 4221 n.a., ref 4221 n.a., ref 4221 n.a., ref 4221 1890-1989 1890-1990 1890-1991 1938-1981 1890-1989 Ilulissat Airport ILUL 04221 4221 69 15 N 54 04 W 69.2500 -54.0667 1999 1894-1995,1999 1890-1995,1999 1890-1995,1999 1890-1995,1999 1999 n.a n.a n.a n.a Nuuk NUUK 04250 4250 64 10 N 51 45 W 64.1667 -51.7500 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1998 1921-1998 1942-1998 1890-1999 Narsarsuaq NARS 04270 4270 61 12 N 48 10 W 61.2000 -48.1667 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1890-1999 1938-1999 1890-1999 Danmarkshavn DANM 04320 4320 76 46 N 18 46 W 76.7667 -18.7667 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 1957-1999 1949-1999 Ittoqqortoormiit ITTO 04339 4339 70 29 N 22 00 W 70.4833 -22.0000 1923-1999 1923-1990 1924-1999 1949-1999 1949-1999 1923-1999 1949-1999 1949-1999 1993-1999 1923-1999 Tasiilaq TASI 04360 4360 65 36 N 37 38 W 65.6000 -37.6333 1894-1999 1897-1999 1894-1999 1894-1999 1894-1999 1894-1999 1897-1999 1897-1999 1958-1999 1894-1999 Iceland Stykkisholmur STYK 04013 4013 65 05 N 22 44 W 65.0833 -22.7333 1890-1999 1952-1999 1952-1999 1952-1999 1952-1999 1890-1999 1890-1999 1991-1999 1965-1999 1890-1999 Reykjavik REYK 04030 4030 64 08 N 21 54 W 64.1333 -21.9000 1866-1999 1949-1999 1949-1999 1949-1999 1949-1999 1870-1999 1920-1999 1991-1999 1965-1999 1949-1999 Vestmannaeyar VEST 04048 4048 63 24 N 20 17 W 63.4000 -20.2833 1878-1999 1949-1999 1949-1999 1949-1999 1949-1999 1881-1999 1890-1999 1991-1999 1924-1999 1890-1999 Hæll HÆLL 04050 4050 64.0667 -20.4167 1881-1999 n.a n.a n.a n.a n.a n.a n.a n.a n.a Raufarhøfn RAUF 04077 4077 ???????????????? ??.?? ??.?? 1921-1999 1951-1999 1951-1999 1951-1999 1951-1999 n.a 1951-1999 1951-1999 n.a 1951-1999 Akureyri AKUR 04063 4063 65 41 N 18 05 W 65.6833 -18.0833 1882-1999 1949-1999 1949-1999 1949-1999 1949-1999 1874-1999 1928-1999 1991-1999 1924-1999 1949-1999 Grimsey GRIM ????? ????? ??????????????? ??.?? ??.?? ?-? ?-? ?-? ?-? ?-? ?-? ?-? ?-? ?-? ?-? Teigarhorn TEIG 04092 4092 64 18 N 15 12 W 64.3000 -15.2000 1890-1999 1965-1999 1965-1999 1965-1999 1965-1999 1874-1999 1951-1999 1991-1999 1924-1999 1890-1999 Norway Ship M MIKE 76900 - 66 00 N 02 00 W 66.0000 2.0000 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 1949-1999 n.a. n.a. n.a. 1949-1999 Tromsø TROM 90450 1026 69 39 N 18 56 E 69.6500 18.9333 1880-1999 1931-1999 1880-1999 1876-1999 1880-1999 1880-1999 1880-1999 1880-1999 1901-1994 1906-1999 Vardø VARD 98550 1098 70 22 N 31 05 E 70.3667 31.0833 1880-1999 1931-1999 1880-1999 1876-1999 1880-1999 1880-1999 1893-1999 1893-1999 1901-1994 1880-1999 Bjørnøya BJØY 99710 1028 74 31 N 19 01 E 74.5167 19.0167 1920-1999 1937-1999 1921-1999 1921-1999 1921-1999 1920-1998 1920-1999 1926-1999 1926-1981 1920-1999 Hopen HOPE 99720 1062 76 30 N 25 04 E 76.5000 25.0667 1945-1999 1948-1999 1945-1999 1945-1999 1945-1999 1946-1999 1920-1999 1945-1999 1945-1994 1945-1999 Svalbard Airport SVAL 99840 1008 78 15 N 15 28 E 78.2500 15.4667 1974-1999 1975-1999 1957-1999 1975-1999 1957-1999 1974-1999 1975-1999 1975-1999 1975-1999 1975-1999 Svalbard Airport reconstructed SVAS 99841 - 78 15 N 15 28 E 78.2500 15.4667 1911-1999 n.a. n.a. n.a. n.a. n.a. 1911-1999 n.a. n.a. n.a. Jan Mayen JAN 99950 1001 70 56 N 08 40 W 70.9333 -8.6667 1921-1999 1937-1999 1921-1999 1921-1999 1921-1999 1921-1999 1921-1999 1922-1999 1937-1994 1922-1999 Myggbukta MYGG 99970 - 73 29 N 21 35 W 73.4833 -21.5833 1921-1999 ?-? ?-? ?-? ?-? ?-? ?-? ?-? ?-? ?-? Climate variation in the European Arctic during the last 100 yearsI. Hanssen-Bauer & E. J. Førland, met.no INTRODUCTION Nordic cooperation has during the later years resulted in several freely available datasets including monthly climate data from the Atlantic/European sector of the Arctic. In the present poster, selected data from the “NARP dataset” (http://projects.met.no/~narp/data_index.html) and the “NORDKLIM dataset” (http://www.smhi.se/hfa_coord/nordklim/nkds.htm) are presented and related to April sea-ice cover in the Nordic Seas and to the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) winter indices. Figure 1 shows the climate stations applied in the present study. Figure 1. Stations applied in the present analysis. TEMPERATURE There are large spatial differences in annual mean temperatures from southern to northern parts of this area (Figure 2, left panel), but the standardised temperature series show similarities (Figure 2, right panel). The first two decades of the century were cold at all stations with measurements in this period. Still, Mann-Kendalls non-parametric test revealed that only a few series (from Iceland and northern Norway) show a statistically significant warming (5% level or better) from 1900 to 2002. Førland et al. (2002) actually concluded that none of the stations in Figure 1 showed a statistically significant warming from 1910-1999. The reason is that the cold period in the beginning of the century was followed by a rapid warming and some warm decades before a period of cooling and finally a new period of warming at the end of the century. At many stations in the area, the thermal optimum of the 20th century was experienced around the 1930s, and the period 1930 to 1960 was generally warmer than the 1961-1990 average. In the north-eastern part of the area the following cooling was rapid. The 1960s were very cold, and mainly followed by a warming trend during the rest of the century. At the southernmost stations in Iceland and the Faroe Islands, there was a more gradual cooling to a minimum around 1980. At the westernmost stations in Greenland, the cooling continued to around 1990. PRECIPITATION The measured annual precipitation in the area spans from about 200mm at the northernmost stations to about 1500 mm at the southernmost stations (Figure 3, left panel). The decadal scale variability is less spatially consistent for precipitation than for temperature (Figure 3, right panel). However, Førland et al. (2002) concluded that all reliable series in the area show a non-negative precipitation trend during the 20th century. According to Mann-Kendall non-parametric test, the positive trends tend to be statistically significant (5% level or better)in a belt from north to south in central parts of the area, while they tend not to be significant in eastern parts of northern Fennoscandia and at the westernmost stations. Positive trends of more than 2% per decade were found at Svalbard Airport, Bjørnøya and Tromsø, while trends from 1.5 to 2% per decade were found at Jan Mayen, Akureyri, Vestmannaeyar and Torshavn. It should however be stressed that reliable measurements of precipitation are difficult to obtain under Arctic weather conditions, and that quality control and homogenization are hampered by the sparse station network. Figure 2.Lowpass filtered annual mean temperature at stations in the Atlantic/ European Arctic given in oC (left) and standardised (above). Figure 3.Lowpass filtered annual precipitation at stations in the Atlantic/ European Arctic given in mm (left) and in % of the 1961-1990 average (above). Atmospheric circulation and air temperature It is well known that temperature variation in the Atlantic/European sector of the Arctic partly is accounted for by the North Atlantic Oscillation (NAO, Hurrell 1995) or the Arctic Oscillation (AO, Thomson & Wallace 1998). Figure 4 illustrates the “temperature see-saw”: In the western part of the area, annual mean temperatures and NAO/AO winter indices are negatively correlated, while they are positively correlated in the eastern part of the area, where the positive NAO/AO phase is associated with an increased advection of mild air from west-southwest. Calculation of correlation coefficients for running 30-year periods during the 20th century gave at Nuuk values from-0.4 to -0.8, and a Vardø values from +0.4 to +0.7, but there were no obvious trends in the correlation coefficients. Figure 5 shows that the AO to a variable degree may account for interdecadal variability: AO may at least partly account for the negative temperature trend in Nuuk and the positive trend in Vardø from the 1960s to the 1990s. The antiphase between east and west in this period is an AO fingerprint, and the AO index has a positive trend in this period. Rigor et al. (2000) concluded that more than half the warming over the eastern Arctic Ocean and the cooling over the Labrador Sea from the 1970s to the 1990s was accounted for by the AO. From around 1910 to the 1930s, on the other hand, there was a warming both in eastern and western parts of the Atlantic/European sector of the Arctic, and there was no significant trend in the AOI (Figure 5). Atmospheric circulation and precipitation The correlation coefficients between annual precipitation and the AO winter index exceed 0.2 only for stations in Iceland, Faroe Islands and Bjørnøya (Figure 6). The correlation coeffecient between winter precipitation and the AOI is usually somewhat higher, and at Bjørnøya it was 0.5. Local precipitation is, however, strongly affected by atmospheric circulation on smaller scales. Hanssen-Bauer and Førland (1998) showed that, at least for localities where the orographic influence on the precipitation distribution is strong, it is possible to model the local precipitation trends fairly well by using local gradients in sea level pressure. Figure 6.Correlation coefficients between the NAO and AO winter indices and annual precipitation at different stations from west to east. Sea Ice and air temperature Vinje (2001) published series of April Sea-ice extent in western (30oW-10oE) and eastern (10oE-70oE) parts of the Nordic Seas/Barents Sea region from 1864 to 1998. These series were correlated to annual mean temperatures from the present dataset (Figure 7). In most cases, there is an anticorrelation between the annual mean temperatures and the April sea-ice extent, and generally the anticorrelation is most pronounced for the sea-ice extent in the sector the station is located. The Greenland stations, however, which are located west of both sectors, tend to show a positive correlation with the ice extent in the eastern sector. We can recognise the Arctic Oscillation see-saw (e.g. Rigor et al. 2002): High AOI is associated with high air temperatures and reduced sea-ice in the Barents Sea region, but low temperatures and extensive sea-ice in the Labrador area. Figure 8 shows that the correlation between sea-ice extent in the Nordic Seas and temperatures in western Greenland not stationary: For 30year periods from the 1960s to the 1990s there is a positive correlation (+0.5) even with the sea-ice in the western area. For 30-year periods in the beginning of the century, however, the correlation was negative (-0.4). Figure 4.Correlation coefficients between the NAO/AO winter indices and the annual mean temperature at different stations from west to east. Figure 5.Lowpass filtered series of the winter AOI and annual mean temperatures in Nuuk and Vardø. Take-away message: There is more in the European Arctic than the AO! REFERENCES: Førland E.J., I.Hanssen-Bauer, T. Jónsson, C. Kern-Hansen, P.Ø. Nordli, O.E. Tveito, and E. Vaarby Laursen, 2002: Twentieth-century variations in temperature and precipitation in the Nordic Arctic. Polar Record, 38 (206), 203-210 Hanssen-Bauer, I. and E.J. Førland 1998: Long-term trends in precipitation and temperature in the Norwegian Arctic: can they be explained by changes in atmospheric circulation patterns? Climate Research, 10, 143-153 Hurrel, J.W., 1995: Decadal trends in the North Atlantic Oscillation: Regional temperatures and precipitation, Science, 269, 676-679. Rigor, I.G, R.L. Colony & S. Martin, 2000: J. of Climate, 15, 2648 Rigor, I.G, J.M. Wallace & R.L. Colony, 2002: Variations in surface air temperature observations in the Arctic, 1979-97. J. of Climate, 13, 896-907 Thompson, D.W.J. og J.M. Wallace, 1998: The Arctic Oscillation signature in the wintertime geopotential height and temperature fields. Geophys. Res. Letters 25, 9, 1297-1300 Vinje, T., 2001: Anomalies and Trends of Sea-Ice Extent and Atmospheric Circulation in the Nordic Seas during the Period 1864-1998. J. Climate, 14, 255-267 Figure 7.Correlation coefficients (R) between April sea-ice extent (western/total/eastern) and the annual mean temperature at different stations. Figure 8.R for running 30-year periods, between April sea-ice extent and the Nuuk and Vardø annual mean temperature.