Tony153,

>"4. It is relatively easy to determine the amount of CO2 in the atmosphere that has come from fossil fuels - burnt by us - and adding to the thickness of the CO2 blanket which, incidentally, has prevented our planet from turning into a snow ball for millennia.
5. What has been keeping us warm on this world, keeps us warmer if it gets thicker - which it is and warmer we are getting."

Apparently you have not recognised the gaping hole in your argument. 'Down in the weed's discussion about climate science, photons, molecules, etc. are irrelevant. You need to show, persuasively, that man's GHG emissions are 1) net bad for the world, and 2) net bad to such an extent that the policies proposed to mitigate the damages will do more good than harm. You haven't even attempted that. So, your arguments are irrelevant. They are no more persuasive than arguments about the existence of a God.

Quote Don
"1) I think it is likely that the climate system has warmed, but the data do not allow us to say accurately by how much, let alone whether or not the warming is harmful to humans or 'the eco-system'"

Don the 'the eco-system' is showing many signs of serious stress and there is plenty of evidence of harm occurring.

Just a few examples off the top of my head:-

There has been a serious decline of the Adélie penguins on Antarctica, where their numbers have fallen from 32,000 breeding pairs to 11,000 in 30 years.

Spruce bark beetles have boomed in Alaska thanks to 20 years of warm summers. The insects have chewed up 4 million acres of spruce trees.

There are numerous examples of bleaching effects on coral due to excessive water temperatures.

Altering the Ph of the ocean affects the ability of a range of shell fish to make their own shells. I saw a show recently where an oyster farmer in America had to alter the Ph of the water in his tanks because they were unable to make shells using the local seawater.

Loss of ice in the arctic reduces the abundance of algae which cascades right up the food chain.

Loss of species due to maintain habitat becoming too warm, for example see the Panamanian golden frog for details.

Tundra is being invaded by low scrub and is reducing the range available to a number of migratory animals such as Caribou.

Spring is now some 15 to 20 days earlier than several decades ago this puts the timing out for a number of species, for example the European pied flycatcher has not changed the time it arrives on its breeding grounds even though the caterpillars it feeds its young are emerging earlier.

Checkerspot Butterflies in Yosemite National Park are not copping with increasing temperature and numbers are all falling sharply in its southern range.

http://oceanservice.noaa.gov/education/pd/climate/teachingclimate/ecological_impacts_of_climate_change.pdf

Recent serious flooding events around the globe are related to record downpours which are one of the anticipated consequences of climate change.

For heaven's sake, Agronomist, why don't you write your own piece so we can see just how you think it should be done? My position is that there is a great deal of uncertainty in all the data. Even Eric Steig, a climate scientist who supports the orthodoxy, has written a long paper about all the uncertainties in ice-core data, and how he hopes that in the future the accuracy can be brought down, which he thinks will happen in time. (See https://www.ncdc.noaa.gov/paleo/reports/trieste2008/ice-cores.pdf) There's scads of other stuff about uncertainty.

At the moment the problem is that there needs to be some kind of independent verifiability of the dating of the ice cores. You can do this if there is a known volcanic eruption (such as Krakatoa or Tambora), but the further back we go the harder it is to find any reliable marker. And the deeper the core the more the annual snow layers become compressed into ice. Yes, everyone is working on how to find ways through, but no, we do not have palaeo data which are exactly comparable to today's instrumental records, such as they are.

Come on, this is widely known. I could say something comparable about each of the 'corrections' that you offer.

To repeat — you write your piece, because you are a scientist and can show the rest of us the right way to do it. I'm sure OLO would publish it.

Don't know whether I should chuck this into the fray or not...but since this thread is taking all comers....and since this hypothesis has made Nature

Methane holes in Siberia?

http://www.nature.com/news/mysterious-siberian-crater-attributed-to-methane-1.15649

"Mysterious Siberian crater attributed to methane

Build-up and release of gas from thawing permafrost most probable explanation, says Russian team."

"But Plekhanov and his team believe that it is linked to the abnormally hot Yamal summers of 2012 and 2013, which were warmer than usual by an average of about 5°C. As temperatures rose, the researchers suggest, permafrost thawed and collapsed, releasing methane that had been trapped in the icy ground.

Other researchers argue that long-term global warming might be to blame — and that a slow and steady thaw in the region could have been enough to free a burst of methane and create such a big crater. Over the past 20 years, permafrost at a depth of 20 metres has warmed by about 2°C, driven by rising air temperatures1, notes Hans-Wolfgang Hubberten, a geochemist at the Alfred Wegener Institute in Potsdam, Germany."

Some people want 100% certainty.

http://www.greenfacts.org/en/climate-change-ar5-science-basis/

http://www.ipcc.ch/pdf/supporting-material/uncertainty-guidance-note.pdf

We are more certain about some things more than ever, we won't ever have absolute certainty, Don.

Don Aitkin, I am well aware that there is uncertainty in measurements of climate. However, as I pointed out above these limitations in measurements do not suddenly stop the Earth from warming.

I don’t write my own piece because I am not really an expert in this area (after all I am an agronomist) and I know my limitations. However, I have sufficient basic scientific expertise to know that you write from a position of almost complete ignorance of the science (at least that is how your articles come across) and therefore your opinions are of little value. I would much rather see you address issues where you more likely have some expertise, such as the political impediments to taking action and how these might be addressed, instead of this climate denier claptrap you write.