Chaotic systems like our climate are not predictable - trends can be observed, cause and effect can be guessed at. You cannot predict the weather in a particular place and on a particular day in 100 years time, though you can be fairly confident that on average it will be warmer if greenhouse gases continue to rise. (Essentially a self referential and therefore inherently correct hypothesis).
You can not trust computer models of climate - they are fine within the limits set by major influences like the Sun, Moon and levels of greenhouse gases in the atmosphere, but they can not say whether it will rain at a specific time and place a month from now. They can be used to predict that summer will be hotter than winter for as long as the Earth's axis remains tilted as it is now - but then we knew that anyway.
Global cooling was predicted in the 1970s, and in fact occurred from 1940 to 1980, a scenario seen as plausible by many scientists of the time. It had also become apparent that the interglacial period we were/are in was/is lasting a lot longer than previous predictions had suggested. So much for predictions and so much for trends.
From timescales of millions of years through 11-year sunspot cycles down to yearly seasons and daily sun-rise, sun-set cycles, variations in the amount of solar energy reaching Earth have a huge influence on our climate. Solar physicists suggest the sun gave off about a third less energy some 4 billion years ago and has been getting brighter and warmer ever since. For most of this time, Earth was actually warmer than today because of higher levels of greenhouse gases trapping more of the sun’s heat.
The ice ages that gripped the planet several times during the past two million years were probably triggered by fractional changes in solar heating caused by wobbles in the planet’s orbit (known as Milankovitch cycles). This cooling and warming was far greater than predicted from the small changes in solar energy reaching the Earth, probably because of the changing sizes of reflective ice sheets and transfers of carbon dioxide between the atmosphere and the ocean. Ice cores from Northern and Southern polar regions show a correlation between CO2 levels in the atmosphere and temperature, but the temperatures sometimes change first. This suggests that warming causes rising CO2 levels in the atmosphere, not vice versa.
Human CO2 emissions may actually be too small to matter, and certainly are small compared with natural sources. CO2 levels have remained within apparently arbitrary limits, we are told, until very recently - presumably balanced by natural absorptions. Terrestrial vegetation consumption by animals and by microbes emits some 220 gigatonnes of CO2 every year. Respiration by vegetation emits another 220 gigatonnes annually. These emissions are balanced by roughly 440 gigatonnes of carbon absorbed from the atmosphere each year by plants during photosynthesis. The oceans release some 330 gigatonnes of CO2 annually, but also soak up slightly more.
Human emissions of CO2 are estimated at 26-27 gigatonnes per year, up 17% from the 1990s (Intergovernmental Panel on Climate Change report, February 2007). Land deforestation and agriculture changes contribute roughly 6 gigatonnes per year. The human contribution is thus about 7% of the total.
CO2 is not necessarily the most important greenhouse gas. The greenhouse effect is caused by certain gases and clouds absorbing and re-emitting the infrared radiating from Earth's surface. It currently keeps our planet 20°C to 30°C warmer than it would be otherwise. Without the greenhouse effect we would (not) be on a cold and sterile world.
Water vapour is the most significant contributor to the greenhouse effect. If you remove all water vapour from the atmosphere apart from the clouds themselves, only about 40% less infrared of all wavelengths would be absorbed. Take away the clouds and all other greenhouses gases, however, and the water vapour alone would still absorb about 60% of the infrared currently absorbed. If CO2 alone were removed, only 15% less infrared would be absorbed. If CO2 were the only greenhouse gas, it would absorb just 26% of the infrared currently absorbed by the atmosphere. So about 50% of the greenhouse effect is due to water vapour, 25% due to clouds, 20% to CO2, with other gases accounting for the remainder. So we contribute 7% of 20% to the greenhouse effect – or 1.4%. Yup – one point four percent. So – we reduce our CO2 output by, say, half and thus make 0.7% difference.
As temperature rises, more water evaporates and the greenhouse effect increases more rapidly still. CO2 is less soluble in warm water - again, a rise in ocean temperature will cause a rise in atmospheric CO2, increasing the greenhouse effect which will in turn warm the oceans even more. The limiting factor is that infrared radiation emitted increases exponentially with temperature, so as long as some infrared can escape from the atmosphere, at some point heat loss catches up with heat retention. Not mankind cutting his paltry emissions.
On longer timescales, going back 600 million years or more, CO2 levels may have been as high as 5000 parts per million, and there are doubts as to whether the CO2-temperature correlation holds up at all. Some scientists suggest that there are major discrepancies during at least two periods whilst some hold that the relationship holds up well.
Data on global temperatures prior to about 1850 is an estimate or reconstruction based on second-hand evidence (ice cores, tree-rings, isotopic ratios etc;) or hearsay (written records, legends, myths etc;). The evidence is sparser the further back we look, and data interpretation often involves a set of assumptions often bordering on guesswork. About 125,000 years ago temperatures may have been about 1°C to 2°C degrees warmer than today and sea-level was probably 5 to 8 metres higher than today. After the last glaciation, global temperatures appear to have peaked about 4000BC (Holocene Climatic Optimum) with average global temperatures about the same as now. From about AD 800 to AD 1300, there was a minor peak called the medieval warm period, again not quite as warm as now. We are currently recovering from what is sometimes called "The Little Ice Age" - when the Thames in London froze over sufficiently to host fairs called Frost Fairs. Put that into perspective however - after the coldest winter (1659), the next coldest winters were 1740, 1879 and 1963 - with 1995 being one of the warmest in recent times.
On such vagueness we are being told to change our way of life to influence our 1.4% effect on global warming. A bit like being asked to guess what is on the other side of a desert, and then push it away using a long, long and very thin pole made of ice. Forget not leaving things on standby – do something significant:-
Turn off all streetlights after midnight.
Give everyone free double-glazing.
Put wind-turbines and solar panels on every house where physically possible. Maybe do it for free too.
Put all our resources into geothermal, hydroelectric, wind, solar, tidal, wave or whatever renewable energy sources there are - short term expense but long-term savings.
Don’t jet of to Kyoto or Bali to drive in motorcades to air-conditioned brightly lit slap-up luncheon hotels to have a conference over a meal with exotic ingredients shipped in from all over the world (at our tax-paying expense) just to tell us to use less power – pick up the bloody phone, or email each other.
Before you criticise someone for driving a big car – find out if he has had a holiday in the last ten years, you may just find out that he has a lower carbon footprint than you do.
Also - remember, not EVERYTHING in the news is news.....
Back in 2007 the UN (United Nations) IPCC (Intergovernmantal Panel on Climate Change) published a report suggesting that the glaciers of the Himalaya region were melting at a rate likely to cause them to dissappear entirely by 2035 or sooner. It's in the IPCC Fourth Assessment Report (938 pages) on the impact of climate change, chapter 10, and it went on to win a Nobel Prize. Their own wording used the term "very high" to describe this likelyhood, and their own terminology guidelines suggest "very high" means greater than 90% certainty.
Unfortunately the report was cribbed from a WWF (World Wildlife Fund) report from 2005, and was not checked for reliability or accuracy by the IPCC. Even worse, the WWF report in 2005 cribbed the information from news stories published in late 1999 in the New Scientist magazine, which in turn were reporting a telephone conversation with a Doctor Syed Hasnain at Jawaharial Nehru University, Delhi. Doctor Hasnain, a scientist in India, has confirmed that his comments were "little more than specualtion"
Doctor Rajendra Pachauri, one of the most influentual "Climate Change Lobbyists", is Chairman of the IPCC. He said initially that the gainsayers were spouting voodoo science. He has since said that the IPCC did NOT check the information as thoroughly as they should have, and as their guidelines demand.
Doctor Rajendra Pachauri, a railway engineer with PhD's in industrial engineering and economics, is also head of The Energy and Resources Institute - advising multi-national companies about the business opportunities in alternative and sustainable energy resource implementation.
The "coordinating lead author of the Chapter on Asia" Dr.Murati Lai admitted that the information was included "purely to put political pressure on World Leaders", and that he was "well aware the statements did not rest on peer reviewd scientific research".
Worse yet - the cited WWF article contained mathematical errors - a loss "over 121 years" was actually divided by only 21, thus causing an enourmous 5.75 times over estimate of the already entirely speculative numbers.
Bottom line is this:
We can look at both Carbon-DiOxide concentration in the atmosphere and also at Mean Global Temperatures for the last 170,000 years. We do this by analysis of plant fossils, and core-samples from Arctic and Antarctic Ice Fields. This data proves beyonf doubt that Carbon-DiOxide concentration in parts per million by volume (C02ppmv) is very closely correlated with Mean Global Temperature (MGT).
There is a caveat - just because two things corealate, it does NOT mean that they are linked directly, or even indirectly. Two examples:
 Since the fifties, car ownership and television ownership are closely corelated - but one did NOT cause the other. They both depended on a third variable, affluence. We find excellent corelation between car ownership and affluence and also between television ownership and affluence. These corelations are directly significant.
 Since the fifties car ownership and life expectancy have both grown and a corelation can be shown. However, nobody would directly link the two, regardless of their corelation. Many would argue that the two are specifically NOT related, even though the data shows corelation.
But - all things considered, it DOES seem that there IS a fairly direct corelation between the CO2 and the Temperature. In fact, over approximately 135,000 years, we find that the MGT varies from -6c (when CO2ppmv is 192) to +2c (when CO2ppmv is 312). The first extreme is during an Ice Age (large ice sheets and minimal vegetation) and the second extreme is from a period with minimal ice cover and extreme vegetation growth.
Approximately 150,000 years ago there was almost no vegetation and, since there were no plants to use it up, CO2 in the atmosphere was high. The world was marginally colder tan today at an MGT of -6c.
Over the next 10 to 12 thousand years the CO2 caused the world to heat up, and at the same time allowed vegetation to increase. So around 135,000 to 140,000 years ago, the world warmed up, the vegetation increased and the CO2 began to be used up by the plants. The world got to around +2c MGT with a high CO2 concentration of around 312ppmv. Over the next 125,000 years, this CO2 was used up by the plants and the MGT fell again to around -6c. Which killed off most vegetation. You see where this is going.....
First - there is a delay between the two factors - the temperature changes lag behind the CO2 concentration changes by something between 2,000 and 4,000 years.
Secondly - the cycle is very long with highs 125k, 250k, 350k and 400k years ago as recent examples - with each high of temperature and CO2 concentration being followed by a slow drop ove the ensuing 100,000 years or so.
So, quite naturally and without the intervention of man, CO2 varies from 192ppmv to 312ppmv.
And quite naturally and without the intervention of man, MGT varies from -6c to +2c.
Now lets get a little closer to the weather. Much more extreme now? Not so.....
Highest monthly sunshine total - sussex July 1911
Lowest monthly sunshine total - London December 1890
Highest 24hr rainfall total - Dorset July 1955
Highest 5min rainfall total - Lancashire 1893
In 1906 a tornado and thunderstorm killed two people in Surrey. There were also 5inch hailstones in Bedfordshire and temperature highs of nearly 35c in Nottinghamshire. Snow was so bad Aberdeen was cut off for three days.
In 1915 England and Wales had one of the wettest four months recorded.
The hottest summer of the 20th century was 1976, hotter than 2003 by 0.5c - and hotter than 1911 by 0.8c.
Way back, though, July 1852 was the hottest since 1659.
Coldest winter of the 20th century - '62-'63, but the cold of '16-'17 was much worse than say '78-'79 or '84-'85.
Of course - there were some REALLY cold winters in 1683-84 and 1739-40.
So - things MAY be warming up. But, if its CO2 levels that are directly causing it, then the trigger is some 2,000 to 4,000 years back, and NOT mankinds post industrial revolution activity.
Looking at the weather in 2010, you don't have to go back too far to beat it:-
The floods in Australia were the worst since..... 1991 - twenty years back.
The Wind Storms in Des Moines were the worst since..... 1998.
Wichita, Kansas had the wettest and hottest summer since..... 1980.
Seattles wind storm damage was the worst since, uh, 2006, 2003, 2000, 1999, 1997, 1995, 1993, 1991 etc
The UK's big freeze was the worst since..... 1995 - or 1981 according to the Meteorological Office.
New York's snowstorms were the worst since..... 1950. The 2009 monsoon rains in India were the lightest since..... 1972 - though they had been light enough to cause drought as well in 1979, 1987 and 2002.
The 2009 "Freeze in Florida" was the worst since..... 1989.
The New Zealand farming drought of 2008 was the worst since.... 1978.
The 2005 Seattle drought was the worst since.... 1992
My point is - weather extremes are not uncommon, neither are they recent phenomena.
The UK's Meteorological Office, in 2009, said the Mean Global Temperature for 2010 would rise to 14.58C - the warmest on record, and a worrying 0.58C above the average from 1961 to 1990. This, they said, was part of a continued trend upwards and, they hoped, would encourage stringent carbon emmission limits at the up-coming Copenhagen meeting.....
At the close of 2010, the same UK Meteorological Office was saying that Global Warming had ceased some 15 years previously. With the exception of 1998, both the UK Met Office and the Climatic Research Unit (University of East Anglia) have data which shows that Global temperatures have remained relatively flat since 1995 - what variations there are in the figures are less than those expected from errors in the measuring system, and are therefore not significant. And that 1998 spike was down to "El Nino", and totally explicable - and known about, expected even.
The UK Met Office has also admitted that the total rise in Global temperature since 1850 (yes - eighteen-fifty) has been less than 0.8C, that's less than a degree in 160 years. They have data which shows that between the 1940's and 1970's the Global mean actually fell slightly.
Michael Mann - he of the infamous "Hockey Stick" chart beloved of Al Gore - has admitted that there was actually a sustained "warm period" around 1000AD when Global temperatures were higher than they are now.
Phil Jones, director of the Climatic Research Unit (University of East Anglia) has said publically that there has been "no statistically significant warming" since 1995.
Kevin Trenberth, head of climate analysis at the US Government National Centre for Atmospheric Research - the IPCC's (UN Intergovernment Panel on Climate Change) main author on climate change, admits that they "can't account for the lack of warming".
But still we are brow-beaten with the fact it's all our fault.
Thousands of delegates fly all over the world, stay in expensive hotels, eat the best food, sit in meetings and then fly back home again, just so that they can tell us to drive less, turn our heating down, turn lights off and pay their pals for our carbon emissions.....