To: Brumar89 who wrote (79597 ) 12/10/2017 2:41:17 PM From: Brumar89 Read Replies (1) | Respond to NOAA Still Falsifying Icelandic Climate Historyen.vedur.is Temperature in Stykkishólmur Stykkishólmur is a village in western Iceland. The temperature (figure 1) has in the long run been increasing at Stykkishólmur during the last 200 years at the rate of +0.7°C per century. This is similar to the general temperature increase in the whole Northern hemisphere during the same period. The warming has been very uneven, dominated by three cold periods and two warm ones. Figure 1. Annual temperature in Stykkishólmur 1798 to 2007. Note that the values prior to 1845 are interpolated from observations at other stations. The confidence is very low for the years before 1830 and the values are preliminary and should not be referenced. The time from 1925 onwards is dominated by a very large cycle that does not show an overall significant warming, although the temperature rise of the last 20 years is considerable. There is also a large decadal variability before 1925. The year 1892 marked the end of a period dominated by a very large year-to-year variability and the end of a long run of very cold years. There was a relatively warm period during 1837 to 1858, and by overlooking the very cold year of 1835 and a few isolated cold months one can identify the interval 1813 to 1858 as a generally warm one. The years 1807 to 1812 were very cold. Although the following warm period was considerably colder than the corresponding 20th century warm period it was noted as a generally favourable time for agriculture and the population of the country increased markedly. The 20th century warm period that started in the 1920s ended very abruptly in 1965. It can be divided into three sub-periods, a very warm one to 1942, a colder interval during 1943 to 1952, but it was decisively warm during 1953 to 1964. The cold period 1965 to 1995 also included a few sub-periods. The so called "sea ice years" 1965 to 1971, a slightly warmer period 1972 til 1978, a very cold interval during 1979 to 1986, but thereafter it became gradually warmer, the last cold year in the sequence being 1995. Since then it has been warm, the warmth culminating in 2002 to 2003. Generally the description above refers to the whole country, but there are slightly diverging details, depending on the source of the cold air. Comparison of temperature in Stykkishólmur, Akureyri and Reykjavík A comparison of annual temperatures at three stations, Stykkishólmur in the west, Akureyri in the north and Reykjavík in the southwest reveals some inter-station differences. The first cold interval, the "ice years", was the coldest of the three in the north and east, but the 1979 to 1986 was the coldest in southwestern Iceland. Figure 2 highlights this by expressing the variability as 7-year running means of temperature. We see the end of the warm period in 1965 and three cold sub-periods during 1965 to 1971, 1979 to 1986 and 1992 too 1995. Figure 2. 7-year running means of temperature at three locations in Iceland, Reykjavík (red trace)), Stykkishólmur (blue trace) og Akureyri (green trace). Kuldakast = cold period. The first of the marked periods was the coldest one in the north (Akureyri), the second one was the coldest in Reykjavík. The cold during the ice years was accompanied by persistent northerly winds and an associated maximum extent of the East Greenland sea ice. The air pressure during this period was generally high – the NAO was in a negative phase. The cold period that started in 1979 was characterised by very low pressure and an extremely positive NAO phase, the NAO phase culminating in 1989 to 1995. The air masses that dominated the weather in Iceland originated over the cold continental areas of Kanada, brought to Iceland by persistent southwesterly winds. In this situation the southwest is anomalously cold compared to the northeast. en.vedur.is Jonsson could not have made it clearer. There has been no overall significant warming since 1925. (At least, up to 2007).It was just as warm in the 1930s and 40s as it has since 1990. There have been two extremely cold interludes, from 1965-71, and again from 1979-86 These warm and cold cycles are clearly evident across the whole country.These climate cycles, and particularly the colder interludes are very well known, and have been the subject of much scientific analysis, for instance here .data.giss.nasa.gov They have replaced the actual temperature data (green) with adjusted data (blue) in their GHCN. The cycles are now gone, and we are left with a steadily rising temperature trend. data.giss.nasa.gov Apologists for temperature tampering claim that it is just all part of an averaging exercise. But this does not wash, because there are no adjustments going the other way anywhere in the region. Indeed, the adjustments all go the same way, cooling the past, for instance at Jan Mayen and Thorshaven (Faroes):In 1965 there was a real and very sudden climatic change in Iceland (deterioration). It was larger in the north than in the south and affected both the agriculture and fishing – and therefore also the whole of society with soaring unemployment rates and a 50% devaluation of the local currency. It is very sad if this significant climatic change is being interpreted as an observation error and adjusted out of existence. https://notalotofpeopleknowthat.wordpress.com/2017/12/09/noaa-still-falsifying-icelandic-climate-history/
