Homogenisation of temperature data is a sore point with climate sceptics as it air brushes out the warmth of the 1930s and the 1870s. In other words, the warmest decades of the 60 to 70 year solar cycle do not show up as they should. Philip Lloyd, writing at https://wattsupwiththat.com/2017/01/28/homogenization-of-temperature-dat… … the raw data that is fed into NASA GISS in order to develop the global temperature series is subject to homogenisation in order to ensure that it does not differ from such things as changes in the method of measuring the mean temperature, or changes in readings because of location etc. This process is supposed to be supported by meta data. Lloyd says the homogenisers are supposed to provide the basis for any modification of the raw data.
The raw data for Cape Town goes back to 1880 – and the warmest years of the record were in the 1930s, as they were in many other parts of the world (see HH Lamb for example). NASA GISS discarded pre-1909 data and the period 1910 to 1939 was adjusted downwards by as much as 1.1 degC. The 1940-1959 data was adjusted downwards by 0.8 degC (average) and the 1969 to 1995 data was adjusted upwards by around 0.2 degC.
Lloyd was curious why this was done and asked for the meta data. The raw data showed a marked step in temperature from the1940s to the 1970s (the cool period of the 60 to 70 year solar cycle) which is also echoed elsewhere. For example, snow in southern and central England was especially heavy in 1947 and 1962 (laying on the ground for weeks). The intervening years were likewise colder than they have been over the last 30 years or so. In the latter period we have had years without any snow – and if it did snow it rapidly melted and mild weather returned. Yet, the raw data was raised at this time. Why?
Lloyd concludes by saying the raw data is probably fairly accurate but the homogenised data is not. It seems pretty clear that temperature data has been tampered with in order to fit into the CAGW meme – for political and money growing reasons. CAGW has become something of a money tree. Where there are big bucks and slush funds being shelled out to potential enemies, such as environmentalists and politicos, there will always be corruption. Unavoidable. However, having said that urbanisation does not help – towns and cities are much warmer nowadays than they were in the past. In addition, rural temperature stations have often been swallowed up by urban sprawl and development. It should not all be regarded as brazen doctoring. The fact remains the process of homogenisation supports CAGW alarmism and for that fact alone it is a dubious activity that attracts deep suspicion. You don't have to be a climate scientist to figure out there is something very wrong with what these people have been doing.
You can also read something similar but this time specifically looking at NOAA temperature data – go to http://notrickszone.com/2017/01/30/robust-evidence-noaa-temperature-data… … which aims straight at the midriff. Tim Ball is having a go at the IPCC at www.wattsupwiththat.com … and so on. With a Trump presidency we are going to see a lot of scientists come out and speak publicly what they have been thinking privately. It's bound to get the usual crowd out to protest – and no doubt they will protest loudly and trump(et) like.
See also http://crev.info/2017/01/cracks-in-the-climate-consensus/ … (link provided by William) which concerns a paper in Nature Climate Change (January) which calls into question the evidence behind the CAGW consensus. He also discusses another paper on deep mantle chemistry which appears to contradict the idea volcanoes always emit large amounts of greenhouse gases and so on. He also says that name calling and ad hominin attacks are not working – sceptics are getting bolder. Hard hitting post.