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With data from Berkeley I made some graphs with trend lines for some weather stations in Denmark. It is interesting to see that they all show a trend of about 0.36C per century. Wonder where IPCCs about 10 times trend comes from? At a first glance I do not see any terrifying "global" warming in Denmark.

GNU-plot Kastrup Airport station id 154572 temperature trend 0.37C/century

GNU-plot Karup Airport station id 154590 temperature trend 0.36C/century

GNU-plot Billund Airport station id 154577 temperature trend 0.35C/century

Update 22nd December 2015
I ceated some more plots for random cities around the World:

• Billund Danmark SID 154577 Trend +0.35C/century
• Johannesburg Airport Southafrica SID 173845 Trend +0.76C/century
• Karup Airport Denmark SID 154590 Trend +0.36C/century
• Kastrup Airport Denmark SID 154572 Trend +0.37C/century
• Kiruna Sweden SID 175331 Trend -0.09C/century
• Kiruna Airport Sweden SID 175328 Trend -0.12C/century
• Murmansk Russia SID 169924 Trend -0.02C/century
• Oslo Blindern Norway SID 174617 Trend +0.27C/century
• Stockholm Bromma Sweden SID 23232 Trend +0.28C/century
• Hamburg Fuhlsbuettel Germany SID 155220 Trend +0.40C/century
• Greenwich Maritime MUK England SID 24900 Trend +0.47C/century

Update 27th December 2015
It has been difficult to find something that approaches raw data files. I got the data from here.
The file I downloaded has these properties:
LATEST - Quality Controlled.zip 201MB (200 989 604 bytes)
From the ZIP I used the data.txt file 654.4MB which has following head:

% File Generated: 15-Nov-2013 16:25:47
% Dataset Collection: Berkeley Earth Merged Dataset - version 2
% Type: TAVG - Monthly
% Version: LATEST - Quality Controlled
% Dataset Hash: 67a656aa1b14deb35b5bcc9edebe9fca
%
% ------------------------------------
%
% This file is a plain text export of a portion of the temperature data contained
% in Berkeley Earth Surface Temperature Analysis.

At this point I am not sure how "doctored" the data are, if at all, but will ask around for more information.
The plots are generated in three steps:

1. Finding the Station ID for city with:
   cat site_detail.txt | grep GREENWICH
   and pick the appropriate SID if the are several options.
2. Extracting the dataset:
   ./extract.php 24900 greenwich_maritime_muk.txt
3. Creating the plot:
   ./long.p greenwich_maritime_muk

The script extract.php:

#!/usr/bin/php5

echo 'Extracting station ID ' . $argv[1] . ' to ' . $argv[2] . PHP_EOL;
echo '-----------------------------------------------' . PHP_EOL;

if (file_exists ($argv[2]))
{
	unlink ($argv[2]);
}

$f = fopen ('data.txt', "r");
while (!feof($f))
{
	$line = fgets($f, 4096);
	if (substr($line, 0, 1) != '%' && strlen ($line) --> 16)
	{
		list ($sid, $ids, $yea, $tmp, $prs, $oth) = explode ("\t", $line);
		if ($sid == $argv[1])
		{
			file_put_contents ($argv[2], $yea . "\t" . $tmp . PHP_EOL, FILE_APPEND);
			echo '.';
		}
	}
}
fclose ($f);
echo PHP_EOL . '-----------------------------------------------' . PHP_EOL;

The plot script long.p:

#!/bin/sh
txt=".txt"
png=".png"
gnuplot << EOF
set term png size 930, 700
set output "$1$png"
set   autoscale                        # scale axes automatically
unset log                              # remove any log-scaling
unset label                            # remove any previous labels
set xtic auto                          # set xtics automatically
set ytic auto                          # set ytics automatically
set title "$1 gnuplot klimabedrag.dk"
set xlabel "Year"
set ylabel "°C"
f(x) = a*x + b
fit f(x) "$1$txt" using 1:2 via a,b
titletrend = sprintf('Trend = %.2f°C/century', a*100)
plot "$1$txt" using 1:2 with lines title "Monthly 1:2", f(x) title titletrend
EOF

Are the data still available?
In case the data have disappeared from the Berkeley website, I may be able to provide you with a copy of my previous download, upon direct request.