G'day,
The data is not tripe. It just isn't very good for camparisons with time. Actually it is dramitically worse than the distribution patterns show. Pick a few weather stations at random out of the 7,000 odd currently being used by some weather reporting authority. Check on the phsical location of the recording equipment and it becomes extremely hard to find a single location where the equipment has been kept in the same general area, let alone under the same conditions.
The biggest expansion of weather stations occurred with aviation. Every airfield needs some basic information about the weather. The trouble is, these weather stations often ended up the town or city official weather station over time, thus moving a previous weather recording station a very long way indeed from where it was prior to the move. Then the airfields got bigger, so the stations kept moving and because of laziness and not wanting to be exposed to extreme weather for very long, the distance between the equipment and those taking the records has been shortened many times and often to the detriment of accurate weather records (on a comparable basis - they are still perectly good for giving a pilot a reasonable idea about whether it is OK to land etc).
Aside from the US, Canada can be included in the list of those countries where the weather records have at least some remote chance of being comparable over time. India has many parts where the records can be determined to also be of some use at least. The UK has good records as does Australia and New Zealand. But still each station has its own problems.
It is interesting that such a mega business is based on data that is so fundamentally flawed and that the only accurate data available, the satellite records of temperatures are pretty much universally ignored or, worse, lampooned. It is also something that if you raise this issue you tend to get dead silence. You do not get a reasoned response. I have been in discussion with some scientists for months working out the validity of methodologies used in their research. Then the assumptions relating to either the heat island effect or to record stations being very poor for use in comparable analysis is raised and that is often the end of the conversation. No further emails answered. No return to telephone messages. Then, because in many cases the scientist realises that a review of their paper or research perhaps might be biased by refusing to answer the person asked to do the review, the next step is often complaints made to the institutions that I have been contracted to.
As to the discounting of urban effect on temperatures, the ASSUMED effect, is often extremely low figures. The Goddard Institute of Dr Hansen fame, and the mouthpiece for NASA with respect to Global Warming was contracted to New York City to fix a very serious problem in the heart of the city. Very accurate data was available that showed the centre of New York had a heat effect of between 5 and 7 degrees celcius in Summer during the day and that this was making the area a living Hell. The New York Authorities wanted a plan to reduce the effect or ways of managing it such as future construction that would funnel winds to reduce the effect, etc. They were open to any suggestions really.
What I found amazing was that this was a commercial question for which the research was being paid to find solutions. For that purpose, it was declared that the effect was in the order of magnitude assessed by New York. At almost the same time another study was being conducted by many of the same people and that study was in relation to Global Warming in relation to Urban Heat Effect for Eastern Continental US. New York was used and it was declared that the Urban Heat Effect was actually a very minor amount, needing an adjustment of 0.1 to 0.3 degrees for part of the summer temperatures. I'm paraphrasing here, and probably getting some of the facts wrong but the overall issues remain valid. How can you state for a commercial project that there is an Urban Effect of up to 7 degrees and for a Global Warming project that it is a very minor effect. One could argue of course that they were measuring different things. One study was for the whole region around New York and the other was only for the very centre. But the data that was accepted for New York included data for the whole of New York and even extending into New Jersey etc until you reached areas that were not uniformly urbanised and for that whole area the numbers still came out at between 3 degrees and 6 degrees.
The other problem that really needs looking at but is very much ignored, is just how the urban effect came to be so discarded in the research that has been coming out for the past ten or so years. For several papers the assumption flows back through papers which in turn relied upon assumptions formed originally by a paper published by the Hadley Climate Research Centre. This was based on a study of winds in China for the most part and an assumption that Urban Effect would be less on windy days than on still days so that measuring temperatures on windless days or in windless areas and on windy days should translate to the real Urban Effect. That all sounds fine but individual areas were not chosen, nor was one single piece of measuring equipment put out. It was simply assumed from the large scale weather activities for an area such as a High Pressure System or Cold Front, that an area was windy or still for several hours or particular nights.
The research indicated, not surprisingly, that there was almost no difference between a "windy" night and a "calm" one.
To my mind, the assumptions used for this research were staggering in just how much was taken for granted. No research was done to find out whether any of the assumptions relied upon were even remotely correct. No enquiry was made to find out whether weather stations for the cities used were in areas that were protected from prevailing large scale weather patterns. The things that were not done and the assumptions made without any prior research that supported it were just breathtaking.
This research paper is referred to in so many global warming papers it just isn't funny. Without wishing to demean anyone or suggest any form of malfeasance (and since I haven't named the report it would be hard to do anyway), the author of the report was a protege of a very senior person in the UK Climate science arena and that person was very proud of the author's achievements.
There is good research out there that suggests vast differences in weather data because of even very minor changes to the environment of the weather recording station. While common sense wouldn't seem to suggest it to be so, simply sealing a road near a weather station has a marked effect on the maximum and minimum temperatures recorded and strong changes to the average wind speeds and directions, especially in dry rural areas.
I had the opportunity to compare weather stations that as best as I could tell were measuring the same area of weather. They were close together geographically (about 2km or 1 1/2 miles apart) and the topography between them was not very different at all. Both had similar surrounding topography. In other words one was not at the end of a valley and the other out on a plain.
They managed to have records taken for more than 15 years overlapping and what happened in the areas around the recording stations was well known even down to very minor details.
A carpark was sealed and the weather station nearby shot up in average temperatures, especially for minimums in winter, which I thought was somewhat counter intiative. Some trees were chopped down and again the temperature changed.
What was interesting is that while one of the stations was an airport station, the area around it changed to what I could say was typically urban, while the other station remained very much rural. The variations between the two stations was more than 3 degrees.
This is not a good test for the urban effect because we only have an overlap of 15 years, there were things that happened at the rural station, such as the carpark that certainly seemed to have an effect. As a control test, it pretty much sucked. But out of all the data I've collected in relation to world's climate and average temperatures, this is the only time I found conditions this good.
There is a much larger study on Berlin and it dates from the 1830s until the 1980s and it shows the rise in average temperatures to be greater than 2 degrees as Berlin urbanised and more than 3 degrees overall. The rise occurred even in the mid 1880s because of the increase in multi storey buildings and paving of paths and roads and this, at least to a certain extent, wipes out any argument that the rise was due to the overall increase coming out of the LIA. But Berlin is an exceptional city in that it urbanised and became a island of heat hundreds of years before most cities because of it being the hub of civilisation for many centuries.
I always like to throw the question relating to the US at someone that is arguing strongly about how NASA and others know what they are doing and have measured urban effect accurately. Me I call them uneducated guesses but generally not in a discussion relating to climate because all that does is end the discussion. It is amazing how few have any idea as to the recorded temperature averages for the US, even when they are supposedly experts on climate change or global warming.
It really is a simple question. Based on NASA and the Goddard Institute data, just how much roughly has the Continental US changed in temperature over the period 1880 to the present? Roughtly 0.5 degree perhaps? 0.8 degrees? One degree? The general answer is 0.8 degrees by the way. When you point out the change is actually a negative figure but not by anything significant, I've found the normal response to be that I have my facts wrong, the data is produced by Exxon-Mobil (why they pick on that particular oil producer I really don't know since it spends more on health research than it did on climate), or that I'm deliberately distorting the truth for my own ends. Since I personally don't have a problem with global warming as a possibility and happily agree that the planet has warmed since 1880, and don't even disagree that methane should be a greenhouse gas, I often wonder why, just because you suggest there may be a contrary view that you are deliberately lying goes together.
Those that attempt to be fair or like to think they are rational scientists (no such thing in my opinion because everyone has their biases and without those biases nothing would be achieved) very often will later comment that the point was valid or express surprise that the figures really do seem to show that the US has cooled a bit. Most instead launch into an attack, very often related to the irony that global warming in a highly industrialised country leads to cooling. The normal argument for that is that sulpher pollution causes clouds downwind of the polluting cities and that's why the US seems to be cooling. It isn't really, it's just the sulpher distorting the readings.
This is all probably way too long but it is at least on point to the thread.
Regards
Richard
