Climate Change and Weather

The UK covered in snow

The UK covered in snow. Click for large picture to open in a new window.

It’s a little colder than usual in the UK at the moment, even though globally this looks like being another warm year – possibly one the three warmest on record. Noticing this reminds me of two particular features of discussions about global warming.

Perspective: In the UK, the winter of 2009-2010 was cold, and the summer was not particularly warm. And this winter 2010-2011 has started off with a strikingly cold period in which temperatures around the UK have been at or close to zero and have fallen to -27 °C in northern Scotland. So from a UK perspective it is shocking to learn that globally this looks like being one of the three warmest years on record. Looking back, there were particularly warm events – perhaps most notably the extreme heat in Russia which led to widespread fires and even a ban on the export of wheat. And to me thus just emphasises the complexity of weather and climate. It is hard for us as individuals to understand the long timescales on which climate evolves, especially in the face of the large variability of weather on daily monthly and annual timescales.

The big effect of small changes: The ‘cold snap’ is actually not that extreme in weather terms – but it has drastically affected life in the UK. There have been road closures, school closures, crops have been left in the field and entire villages have been shut off. If this kind of weather became more common in the UK, even though it would represent only a relatively minor climate change- it would change the way we live and work – and cost a good deal of money as we adapted. Similarly, if equally minor changes in weather patterns became more common in poorer regions then it is easy to see how even relatively minor changes could be catastrophic.

10 Responses to “Climate Change and Weather”

  1. rogerthesurf Says:

    ” So from a UK perspective it is shocking to learn that globally this looks like being one of the three warmest years on record. ”

    Seeing as how similar conditions have effected Europe, N America and Asia, did it ever occur to you that we may be being taken for a ride?

    Cheers

    Roger

    http://www.rogerfromnewzealand.wordpress.com

  2. protonsforbreakfast Says:

    Roger

    Yes. It does occur to me. But (a) having met some of the people involved at the Surface Temperature Workshop last September and (b) having understood a little about this subject I think it is unlikely.

    Looking at your blog I see that your view is that there are natural climate changing factors the causes of which we are ignorant. These factors are affecting the climate but there is nothing we do can do about them. And CO2 isn’t one of them. I hope I have summarised your position fairly.

    I don’t think that’s a rational position. It is basic physics that CO2 is an infra red active gas, and basic physics that tells us we are putting more than 8 million tonnes of CO2 into the atmosphere every day. Together these imply that there will be >someno effectThere has historically been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period (200 mya), average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm — about 18 times higher than today.ever< lived in a world with so much CO2. YOu mention the case of farmers in Greenland who left 500 years ago because of the cooling climate. I don't know the cause of this change – but I do know that they had somewhere to go – they probably got on a boat and went back to Denmark or on to Canada. For the population of Bangladesh, there will be no where to go in the face of even a modest sea level rise.

    All the best

    Michael

    • rogerthesurf Says:

      Michael,

      Thanks for your reply.

      I hope you enjoyed my blog.

      What it really trying to say, and I think you missed this important point, is that there is no reasonable evidence for anthropogenic climate change.

      If you wish to take a more scientific view, I suggest you look at the “anthropogenic CO2 causes Global Warming” hypothesis and ponder what proof there is for this.

      When one considers a hypothesis such as this (and the whole of AGW relies on this hypothesis for its foundation), in the absence of any empirical proof of causation, one should consider which other hypothesis fit the known facts.
      If there are other hypothesis’ which fit the facts, one (in order to show that your hypothesis is the correct one), needs to explain why/how the other hypothesis does not fit the known facts.
      However if you cannot do that for all the other hypothesis, then your own hypothesis is unlikely to be true.
      Also there may be events which disprove your hypothesis, such as in our case having warm periods in history where we know anthropogenic CO2 was not present.
      Consequently, if there is no reliable causal link between CO2 and the current warming to support the current hypothesis, it is unlikely that the hypothesis is valid.

      The above is what my blog says except that it is couched in lay persons terms.

      Do you still think I have an irrational position?

      Cheers

      Roger

      http://www.rogerfromnewzealand.wordpress.com

  3. protonsforbreakfast Says:

    Roger

    Thanks for expanding on your position. I still disagree with you. Your position is basically that (a) there is current warming but (b) there is no evidence that it is caused by anthropogenic emissions.

    Following (a) and (b) above, my position is that (a) there may or may not be current warming but (b) we >knowsome< effect on Climate Forcing.

    Expanding a little: (a) there does appear to have been some warming, but the evidence is hard to gather. There are other effects – e.g. arctic ice – which indicate that 'something is happening'. (b) It would be extraordinary if 30 billion tonnes of CO2 per year – around 3% of the total amount of CO2 in the atmosphere – conspired to have no effect at all. Is that what you believe?

    All the best

    Michael

  4. rogerthesurf Says:

    michael,
    Not quite right,

    There is not only no empirical or any other reasonable evidence to show that this current warming (which is simply one of many in historical times) is caused by CO2, but the fact that there are historical (and prehistoric) warmings of greater magnitude, when CO2 was lower in concentration and none of it anthropogenic, make it unlikely that CO2 is the culprit this time.
    In fact, in order to make a start pointing the finger at CO2 it would be scientifically neccesary to ascertain the causes for the previous warmings and then conclusively prove that they are not active at the moment. If you have a scientific paper along those lines, I for one would like to see it.

    Just to put your numbers in perspective, try getting a litre of water and then try and add .0012% of something to it and you will get some sort of idea what you are talking about. Maybe one grain of salt may be as close as you can get.

    Also bear in mind that CO2 is a life giving gas and modest increases of CO2 concentralions, up to 10,000 ppmv have a beneficial effect on agriculture. I have references for that as well.

    Cheers

    Roger

    • Michael Says:

      Roger

      It is a simple fact that CO2 acts as a greenhouse gas. Even at its tiny concentration it makes the air opaque at certain wavelengths. Basically at these wavelengths the atmosphere looks like a fog and the seeing distance into the fog is just a few tens of metres. We have often seen these effects in experiments measuring temperature by infra red techniques. It would be extremely odd if putting 30 billion tonnes of this stuff into the atmosphere had no effect – the question is “How big is the effect?” and “Is it a net warmer or a net cooler?”. I don’t think people really know what the effect will be, but the consensus seems to be that some warming is likely. Time will tell. I really can’t think why you want to deny this.

      Regarding the ‘beneficial’ effects of CO2, some plants to do indeed grow better at elevated CO2 levels, but many ocean organisms do not grow well in the consequently acidified ocean. Additionally, 1000 ppm is the borderline for CO2 to affect concentration: our air conditioning at NPL is triggered by CO2 levels above 1200 ppm. 5000 ppm is the US workplace exposure limit. 10,000 ppm may be good for plants but it would not be good for people!

  5. rogerthesurf Says:

    Yes I beg your pardon.
    I was a decimal place out.
    My sources for the information are as follows.
    Optimum Glass House CO2 concentrations http://api.ning.com/files/X-APctmkiwvgEI5fT6iiGjWFvKNX*cWuzeO4qmDVbgA_/Greenhouses.CarbonDioxideInGreenhouses.pdf
    Exhaled breath concentration http://www.biotopics.co.uk/humans/inhaledexhaled.html
    5000ppmv is acceptable for work places (American Conference of Governmental Industrial Hygienists).
    3000ppmv for residences (Canadian exposure guideline for residential buildings)

    To show that CO2 has greenhouse properties in the lab, does not imply in any way the the net effect will be the same in the atmosphere.

    “The total amount of CO2 humans have added to the atmosphere in the last 100 years has upset the radiative energy budget of the Earth by only 1%. How the climate system responds to that small “poke” is very uncertain. The IPCC says there will be strong warming, with cloud changes making the warming worse. I claim there will be weak warming, with cloud changes acting to reduce the influence of that 1% change. The difference between these two outcomes is whether cloud feedbacks are positive (the IPCC view), or negative (the view I and a minority of others have).” Dr Roy Spencer at http://hockeyschtick.blogspot.com/2010/07/dr-roy-spencer-open-to-possibility.html

    What he is saying and there seems to be consensus that the direct effect of the weak greenhouse effect from CO2 is too small to effect the climate, but what is claimed, is the effect that it might have on the biggest greenhouse gas H2O.

    A feedback scenario may be as follows.

    Anthrogenic CO2 concentrations increase – slight warming of atmosphere – Extra heat causes increase in evaporation from oceans etc. – More clouds form reflecting solar radiation back into space. Atmosphere cools.

    IPCC etc claims that it will amplify the greenhouse effect, others say that the feedback will be negative. That is H20 will tend to nullify any effect from CO2.

    The truth is as Dr Spencer says, is that no one actually knows, and this is what I am talking about when I say there is no significant evidence for the “anthropogenic CO2 causes Global Warming” hypothesis.

    If there was a positive feed back, I suspect that the climate would be historically a lot more erratic than it is now.

    Cheers

    Roger

  6. Michael Says:

    Roger

    I think we agree. However you regard the fact that no link can be >proved< as a rationale to take no action. I however regard the fact a link of some sort is likely to eventually become manifest as a good reason to take action now.

    Have I summarised our differences fairly?

    Michael

  7. rogerthesurf Says:

    Michael,

    There is just one other thing.

    The cost of meeting the CO2 emission reductions and wealth transfers as specified by the IPCC.

    I have a background in economics, and I have a reasonable learned position on this.

    Have you thought about it?

    What if the cost is so high that we end up ruining our economies which means poverty and starvation for us and our families.

    Should we do that to ourselves on account of the current “evidence” for global warming?

    Cheers

    Roger

    http://www.rogerfromnewzealand.wordpress.com

    • Michael Says:

      Roger

      If the cost of action is too high, then clearly we won’t take any actions and we will instead pay the (potentially much larger) costs later when they become unavoidable.

      If you ask how much we should spend to avoid climate change consequences then there is a range of possible answers. Well one answer is ‘Nothing’. This is unlikely to be optimal, but represents a stance of deferring any costs as long as possible in the hope that they will not be as large as some fear. Another answer would be ‘Lots’ which could bankrupt us. I think this simply won’t and can’t happen – economics has its own imperatives. But the final possible answer is ‘something’. Surely there are enough reasons to be concerned to take some modest steps to reduce carbon emissions, steps which would make sense for other reasons as well.

      Economically, its a matter of paying the full costs of carbon emissions now, or deferring them. Its our choice.

      All the best

      Michael

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