Summer Temperature Trends In Greenland
By Paul Homewood
https://notalotofpeopleknowthat.wordpress.com/2015/09/19/dmi-show-greenland-was-warmer-in-1930s/
According to the official numbers from DMI, annual temperatures across Greenland were just as high in the 1930s and 40s as they have been in recent years. The only exception was the unusually warm year of 2010.
But what about summertime temperatures? Since that is when most ice melt occurs, this time of year is perhaps the most relevant.
Based on the actual temperature record, (and not the adjusted version), we can see that the pattern is similar to the annual trend for both Nuuk and Angmagssilik, on the west and east coasts respectively.
Again, temperatures since 2000 for the main part are, if anything, lower then the 1930s and 40s.
http://data.giss.nasa.gov/gistemp/station_data_v2/
There is nothing here to suggest that the climate in Greenland in the last century is any more than a reflection of natural cycles such as the AMO.
NOT A LOT OF PEOPLE KNOW THAT 
Same in Alaska
Noting the 41 year-long cooling trend in Fairbanks, AK. Courtesy CAG.
http://www.ncdc.noaa.gov/cag/time-series/us/50/USW00026411/tavg/ytd/12/1895-2016?base_prd=true&firstbaseyear=1901&lastbaseyear=2000&trend=true&trend_base=10&firsttrendyear=1975&lasttrendyear=2016
If the link doesn’t bring up the trend line since 1975, plug it in.
Other than that, obvious is the flip from a cool cycle prior to the late 1970’s, and a warm cycle post. There are two periods here; one cool, the other warm.
What’s next?
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the surface temperature time series is known to contain dependence and persistence. these properties violate OLS assumptions. therefore, OLS trends computed under these conditions are spurious. robust tests for trends should be used to validate OLS results.
http://papers.ssrn.com/sol3/Papers.cfm?abstract_id=2776867
“…robust tests for trends…”
Even then, time is an “explanatory” variable but never a “causal” variable. Therefore, trend analysis of a univariate series can contribute little to scientific understanding.
Regression of cyclic events is inherently inaccurate as they are non-linear by definition.
If one looks crudely at the temperature anomaly data from most sites it seems that there is a natural warming long-term trend of between 0.6 and 1.0 degK/century. The cyclical changes appear to be almost pure but noisy sine waves if the average rise is removed.
Would an analysis of the Fourier type be more relevant than linear regression in quantifying the underlying warming trend?
“time is an “explanatory” variable”: it’s a great pity that statisticians didn’t invent neologisms for some of their notions instead of using everyday words, but with a specialised change of meaning. “significant” is another example.
“…a great pity…”
It is true of every science that the originators used common words in uncommon and misleading ways. They often misled themselves! It is also true that words were sometimes used deliberately to convey an idea which turned out to be nonsense. For example, some rocks are said to be “acid” when there isn’t a stray hydrogen ion in them.
Of course, the point is that “unfolding time” in a particular situation can only be a proxy for something during that time period. The leaves are unfolding in my garden; but it is not time that is causing their growth – it is the conditions of spring, and all the facts of botany. There will be a plentiful supply of time in winter – but that will then be associated with a trend of falling leaves.
The graphs are intriguing, as much for what they say as what they don’t. It amazes me that with all the crying about temperature changes in the past 10 years, there would actually be data gaps during that period of time. How can you show a tend if you don’t maintain the data? Or is it left out for a reason? My guess is that the original producers of the data didn’t like what they were seeing so they stopped paying attention.
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http://berkeleyearth.lbl.gov/regions/greenland
roflmao
Salesman Mosh on the job again
Trying to sell the lemon that is BEST. !!
Click to access greenland-TAVG-Trend.pdf
In combined temperature series from southwest Greenland from the period 1784-2005, the 1930’s and 1940’s were the warmest decades and the 1810’s the coldest – not least due to unidentified large volcanic eruptions in 1809 and the Tambora eruption in 1815.
http://www.dmi.dk/en/klima/klimaet-frem-til-i-dag/groenland/
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