Climate science and the UK Climate Change Act

The Climate Change Act of 2008 is, supposedly, underpinned by the findings of climate science, and riding herd on these findings is the Climate Change Committee (CCC), which reviews the state of climate science whenever a new carbon budget is published to see whether any significant changes have occurred. Here we briefly review the CCC’s latest assessment, which accompanies the fifth carbon budget. We find that few if any of the CCC’s conclusions are backed up by hard evidence and that some of them are the opposite of the truth. Yet they still underpin the Climate Change Act, which continues to govern the UK’s long-term energy policy.

Listed below without comment are the CCC’s conclusions on climate change, reproduced from the CCC’s fifth carbon budget report . These are the conclusions on which the UK government is basing multi-billion pound decisions:

The evidence that global warming is happening, driven by human activity and with large potential impacts, is supported by many lines of research and agreed by the world’s leading scientific bodies. Much of the information presented here is covered at length in the latest assessment by the Intergovernmental Panel on Climate Change (IPCC AR5)

It is clear that the climate is changing as a result of greenhouse gas emissions. This is leading to rising temperatures and sea levels, retreating ice and other changes to the natural environment. Global average temperature has risen around 0.9°C and sea level around 20cm since the late 19th Century:

• The basic fact that greenhouse gases in the air warm the surface of the Earth has been understood for over a century and is well-established.

• Greenhouse gases are being emitted by human activities (principally carbon dioxide from fossil fuel burning) at an increasing rate and are accumulating in the atmosphere. Emissions of other air pollutants have a net cooling influence, partially offsetting greenhouse warming to date.

• Trends in climate are also influenced by natural factors, including solar variations, volcanic eruptions and natural cycles within the climate system (such as El Niño).

•  Global average surface temperature is now about 0.9°C above late-19th Century levels. Observed warming is not uniform and has led to many other changes including changes in rainfall patterns, rising sea levels and the loss of ice from Greenland and Antarctica. Carbon dioxide emissions are also acidifying the oceans.

• The pattern of global warming over the 20th Century matches that expected from natural and human factors combined, and not that from natural factors alone. Human activity has clearly been the dominant driver of global temperature rise since at least the 1950s. Many impacts are already being detected across the world, from changes in extreme weather and ecosystems to a slowdown in productivity gains for some key crops.

• Scientists are highly confident that, among other impacts, climate change is bleaching coral on reefs worldwide; greening and fruiting trees earlier in the year across Europe; reducing river flows across South Western Australia; forcing plant and animal species towards the poles and to higher elevations around the world; and negatively impacting those living in the Arctic.

• There has been a negative effect on the global growth in productivity of some key crops, with a reduction of 2 %/decade (0-5 %/decade) for wheat, and 1 %/decade (0-3 %/decade) for maize. Some crops in Europe and southern South America have experienced gains due to climate change, while South Asia and wheat in Europe have incurred losses.

• European heat waves as strong as in 2003 (when crop yields fell, power stations were shut down due to overheating and the heat-related death toll ran into tens of thousands) are estimated to have been made at least twice as likely by human activity. A recent update suggests the warming since 2003 now makes it ten times more likely to occur again.

• The coastal surge brought to Manhattan by Hurricane Sandy in 2012 was made 20cm higher by sea level rise, increasing losses in New York by 30%. In addition, the above-average sea surface temperatures at the time increased its wind speeds and rainfall.

These impacts give an indication of the widespread and pervasive nature of climate risks.

Even those with only a rudimentary knowledge of the facts will be able to find holes in these conclusions big enough to drive a bus through. Specific examples include the claim that wheat and maize crop yields are declining, which was debunked in Euan Mearns’ Food, Population and Energy post, the claim that climate change is impacting extreme weather events – something that not even the IPCC agrees with; see Roger Pielke’s post on the subject – and the claim that 20cm of sea level rise increased damage losses from Sandy by 30% in Manhattan. But not a word is said about the global warming “pause”, or about the fact that climate models no longer match observations, or about the numerous recent estimates of climate sensitivity which suggest that the IPCC’s 3 degrees C estimate may be up to two times too high.

Yet these myths and others like them, such as the Greenland ice sheet collapsing into the sea, continue to be perpetrated, and under the provisions of the Climate Change Act they continue to drag the government’s energy policy around by the nose. As to what can be done about it, the opinions of the CCC will not change as long as it remains populated entirely by greens (see the CVs in the CCC fifth carbon budget report). A faint chink of light is, however, offered by the Climate Change Act itself, which authorizes the Secretary of State to “amend the (80% by 2050 target) …. if it appears to the Secretary of State that there have been significant developments in ….. scientific knowledge about climate change.” Well, there have indeed been some significant developments since the Act was adopted in 2008, but thanks to the CCC Amber Rudd may never have been told about them. Whether her successor Greg Clark is aware of them is unknown, but if he isn’t someone should tell him.

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32 Responses to Climate science and the UK Climate Change Act

  1. David Ellard says:

    From carbon-13 isotope analysis, use of Henry’s Law to calculate ocean uptake of atmospheric CO2, and current knowledge of the carbon cycle, it is possible to demonstrate that the global rate of photosynthesis has increased by 12% as a result of anthropogenic CO2 contributions. I don’t know if wheat or maize have a response to CO2 notably different from other photosynthesisers, but the increase in yields is likely to be of the same order as the rest.

    I can show the calculations, but would require a whole post to do so, if anyone is interested!

    • Alex says:

      If you have the link, it would be handy.

      Plant growth is always constrained by something – amount of nutrients, amount of light, or amount of CO2. Greenhouses can help remove these constraints.

      A 12% growth would imply that CO2 is a major constraint. I would have thought light and nutrients were more significant, but I’m not a biologist.

      • David Ellard says:

        Well, CO2 levels have risen about 30-35% since 1900, so the dependency of photosynthesis is obviously less than first order in CO2. Light isn’t much of a constraint actually (photosynthesis uses only a tiny fraction of solar radiation), but nutrients are, especially in the deep oceans (which is why seeding the oceans with iron filings causes plankton swells).

        But the importance of CO2 can be seen from the existence on Earth of (non-polar) deserts. Deserts are the result of dry conditions, of course, but in fact low CO2 and low rainfall are one and the same constraint on plants. This is because plants draw CO2 from the atmosphere through stomata (microscopic holes in their leaves). The process of air exchange brings CO2 levels in plant tissues (where it is depleted) towards those in the atmosphere but, by the inevitable laws of thermodynamics, also brings H2O levels in plant tissues towards those of the surrounding air (which in deserts is dry).

        Plants can only survive certain combinations of dryness/CO2 concentration. Making the air more humid and/or increasing its CO2 content will allow plants to survive where previously they were unable to. Hence why, in drought-stressed regions, adding CO2 to the air boosts photosynthesis and plant growth.

        • Willem Post says:


          CO2 is piped into greenhouses in the Netherlands with great results for flowers, fruits and vegetables.

          CO2, water, friable soil (not clayish), pH, and nutrients are the main ingredients for plant growth.

          If all are present in proper amounts crops will be plentiful.

        • robertok06 says:

          “Impact of CO2 fertilization on maximum foliage cover across the globe’s warm, arid environments”
          Authors: Randall J. Donohue, Michael L. Roderick, Tim R. McVicar, Graham D. Farquhar

          Geophysical Research Letters, Volume 40, Issue 12, 28 June 2013 Pages 3031–3035

          Satellite observations reveal a greening of the globe over recent decades. The role in this greening of the “CO2 fertilization” effect—the enhancement of photosynthesis due to rising CO2 levels—is yet to be established. The direct CO2 effect on vegetation should be most clearly expressed in warm, arid environments where water is the dominant limit to vegetation growth. Using gas exchange theory, we predict that the 14% increase in atmospheric CO2 (1982–2010) led to a 5 to 10% increase in green foliage cover in warm, arid environments. Satellite observations, analyzed to remove the effect of variations in precipitation, show that cover across these environments has increased by 11%. Our results confirm that the anticipated CO2 fertilization effect is occurring alongside ongoing anthropogenic perturbations to the carbon cycle and that the fertilization effect is now a significant land surface process.

        • Pedro J. says:

          This thread reminds me the famous cartoon about the queue of simple but wrong answers. There is a couple of interesting papers about this matter. Firstly a review from 2010

          The impact of global elevated CO2 concentration on photosynthesis and plant productivity []

          “The adaptive acclimation responses of plants to changing climate remain contradictory. This review focuses primarily on the impacts of global climate change on plant growth and productivity with special reference to adaptive photosynthetic acclimative responses to elevated CO 2 concentration. The effects of elevated CO 2 concentration on plant growth and development, source–sink balance as well as its interactive mechanisms with other environmental factors including water availability, temperature and mineral nutrition are discussed.”

          Increasing CO2 threatens human nutrition []

          “Dietary deficiencies of zinc and iron are a substantial global public health problem. An estimated two billion people suffer these deficiencies, causing a loss of 63 million life-years annually. Most of these people depend on C3 grains and legumes as their primary dietary source of zinc and iron. Here we report that C3 grains and legumes have lower concentrations of zinc and iron when grown under field conditions at the elevated atmospheric CO2 concentration predicted for the middle of this century. C3 crops other than legumes also have lower concentrations of protein, whereas C4 crops seem to be less affected. Differences between cultivars of a single crop suggest that breeding for decreased sensitivity to atmospheric CO2 concentration could partly address these new challenges to global health.”

    • Dave Rutledge says:


      It is Euan’s calI, but I would be interested in a post on this topic.


    • Richard says:

      “use of Henry’s Law to calculate ocean uptake of atmospheric CO2”

      Use Henry’s law to calculate ocean uptake of atmospheric CO2 then. Let’s see if you can do it.

  2. Leo Smith says:

    If they ‘need’ to amend the act, they will ‘find’ the science…

    Inside of what used to be DECC there is a hard core of pro nuclear people, not because they are fans, but because it’s the only reasonable way to meet low carbon budgets.

    • Willem Post says:


      This is about RE scare-mongering to get subsidy money and other bennies by vilifying fossil fuels. About 6 million people die from smoking EACH YEAR.

      RE systems folks and their shills know their RE systems produce weather-dependent, variable, intermittent, expensive energy during their short useful service lives.

      The RE systems could not stand on their own without life support from the OTHER generators, which have done just fine without such RE energy since about 1800.

      Climate change “artists” do not mention deforestation, urbanization, and industrial agriculture, and pollution having effects on the climate. If Europe and the US were sparsely populated, most of their land area would be covered with hundred-plus-year-old trees.


  3. jim brough says:

    Very early in my university career as a microbiologist I learned that as the temperature of water increases, dissolved gases are liberated. CO2 included.
    A global warming episode unrelated to anthropological CO2 emissions will release oxygen and CO2 from the oceans to increase atmospheric CO2 levels.

    Civilisation is not possible without CO2 emissions.

    Try making solar cells. Or any of the minerals from lead to lithium to store the energy for distribution, and the steel, concrete and concrete needed to distribute it…………………..
    without CO2 emissions.

  4. Climate alarm is a zombie army. It relies on arguments that either have been refuted outright (extinctions, crop and vegetation loss) but somehow limp on, have found little to no support (stronger storms), or are completely absurd and presented in a massively misleading way. The poster child of the latest case is ice sheet and glacier collapse: we routinely hear that this or that mass of ice ‘tips’ above whatever temperature, that there are only 10 years left before Greenland hits the ‘tipping point’, that such a rise in sea level ‘threatens the survival’ or ‘could inundate’ cities around the world, and suchlike trash. What we don’t hear, but the models and everybody in the business acknowledges, is that tipping it would take *thousands of years* for them to melt down.

    (As for non-polar glaciers, all of them add up to a whooping 40 cm worth of sea level. They don’t say that in the documentaries).

    Some of the claims of increased weather losses and so on look good on paper, so at least they deserved consideration. Certainly it makes sense that precipitation would increase in a hotter, more humid atmosphere, and that perhaps this would lead to worse floods and so on. But as evidence accumulates, bad hypotheses should be discarded.

    Science is not only about making hypotheses. It’s also about testing them – and discarding the bad ones. As a hypothesis or theory, warming-induced catastrophe is an overwhelming failure.

    For example, it intuitively makes sense that more people will die in heat waves in a warming world. But it turns out heat-related mortality has been declining. Whatever AGW signal there is must be extremely weak, but this doesn’t stop the usual suspects from cherry-picking the one heatwave in 2003 that did kill a lot of people. (I wonder why they don’t analyze the thousands of deaths in 2004, 2005… oh, wait – those deaths didn’t happen).

    There are also physical reasons to think the impact will be small. Greenhouse warming is expected to be strongest near the poles, at night, and in winter – hardly the times and places where people suffer a heat stroke. So far reality has met theory, except in the case of the southern pole which for some reason is warming more slowly (if at all) than the rest of the globe, not faster.

    In any case, what matters is not whether there are negative impacts, for one can find negative impacts for everything under the Sun including sex and peanut butter. What matters is the NET impact, counting costs as well as benefits, and especially the MAGNITUDE of such impacts.

    You have to look at the big picture. There’s always a flood somewhere. Droughts are always getting worse somewhere. The world is a big place ripe for cherrypicking. But, there are companies called insurers tracking how much is claimed in weather disasters per year, and indeed there is a clear trend – just not one the climate bureaucrats will like.

    And this is insured losses, which are smaller than total losses. But as the world develops a greater share of assets is being insured, so if anything this introduces an upward bias in the chart! Yet, the trend is down, and every year that passes only makes the result stronger. 2014-16 is looking like the LOWEST three-year period on record! And yet, it’s also the period with the highest temperatures.

    By the way, the CCC mentions storm surge. Again, it seems to make sense that if sea level is higher, losses from such weather disasters will be greater than they would otherwise have been. It also seems high sea surface temperatures are necessary for hurricanes so perhaps there is a link. But if the trend for *all* disasters combined is strongly negative, the only possible conclusions are:
    a) Warming has also worked to reduce storm-caused damange, for example by reducing the equator-pole temperature differential.
    b) Perhaps warming indeed has a net negative impact overall on, but the size of this effect is negligible – so it’s been overwhelmed by increased use of doppler radar, better building codes, etc.

    Imagine for the sake of analogy that warming triples the cases of polio. In the XIX century that would have been a catastrophe – today it would be irrelevant.

    And again, what really matters is magnitude. Climate skeptics have the bad habit of trying to ‘prove’ that thing X is not happening *at all*, which is a bit meaningless if you think about it. The question is, to what degree is thing X happening? What are the consequences? If the trend in weather disasters was upwards, perhaps we could reduce projected 2100 weather losses to 0.2% of GDP rather than 0.3%.

    The only people who would spend $100 trillion to achieve that are those using others’ money.

    Let me finish by reposting here a bet I proposed on other blog. The other person initially agreed, but after realizing he’d made a mistake he backed out in a series of comments and emails. It’s still open to anyone willing to participate with his real name (you can find my email with a bit of googling).

    ‘I bet crop yields will be higher every decade than the previous, until we’re both dead (and thereafter probably, but we won’t be there to see it).

    I bet weather disasters will continue to decline as a share of GDP.

    I bet not a single town over 10,000 will be abandoned due to sea level rise before 2100.

    I bet not a single island over 1,000 will suffer that fate, again in the XXI century.

    I bet the world’s green mass will be higher every decade than the previous, again indefinitely.

    I bet verified species extinctions this century will be less than in the XIX or XX centuries.

    I bet on those things no matter how much carbon we end up emitting, how much 0f that carbon remains in the atmosphere, or how much we warm up.’

    • jfon says:

      How old are you?

    • A C Osborn says:

      I assume that all bets are off if it gets a lot colder though, especially Crop yields?

      • According to the German Advisory Council on Global Change, which came up with the 2C “dangerous interference” threshold back in 1995, the Earth can tolerate mean temperatures of between 9.9˚C and 16.6˚C. With the current mean global temperature around 15.3C this means that it can tolerate an Ice Age but not an additional 1.3C of warming. So a little bit of warming is bad but a lot of cooling is OK.

        • Willem Post says:


          Western Europe experienced a general cooling of the climate between the years 1150 and 1460 and a very cold climate between 1560 and 1850 that brought dire consequences to its peoples.

          The colder weather impacted agriculture, health, economics, social strife, emigration, and even art and literature.

          Increased glaciation and storms also had a devastating affect on those that lived near glaciers and the sea.

          Impact on Agriculture

          Lamb (1966) points out that the growing season changed by 15 to 20 percent between the warmest and coldest times of the millenium.

          That is enough to affect almost any type of food production, especially crops highly adapted to use the full-season warm climatic periods.

          During the coldest times of the LIA, England’s growing season was shortened by one to two months compared to present day values.

          The availability of varieties of seed today that can withstand extreme cold or warmth, wetness or dryness, was not available in the past.

          Therefore, climate changes had a much greater impact on agricultural output in the past.

        • Pedro J. says:

          “According to the German Advisory Council on Global Change, which came up with the 2C “dangerous interference” threshold back in 1995, the Earth can tolerate mean temperatures of between 9.9˚C and 16.6˚C. With the current mean global temperature around 15.3C this means that it can tolerate an Ice Age but not an additional 1.3C of warming. So a little bit of warming is bad but a lot of cooling is OK.”

          Your are committing the same mistake as with the GdV 100% advertisement: confusing a political claim with a technical one. 2ºC is just a political threshold; a reference to bring a plan for limiting CO2 emissions. An unstoppable climate change could happen with 1.7, 2 or 3 degrees; Nobody knows exactly.

          Another thing is that when people say an Ice Age would be worse, they forget about time scales. With CO2 500-600 ppm we are doomed within a couple of centuries, at most.

          • Your are committing the same mistake as with the GdV 100% advertisement: confusing a political claim with a technical one. 2ºC is just a political threshold.

            So we’ve been using political thresholds that have no basis in science to justify the expenditure of trillions of dollars.

            I’m reminded of the bill put before the Illinois legislature in 1897 which sought to have the value of pi set equal to 3.2. The bill didn’t pass because of the last-minute intervention of Professor C. A. Waldo of Purdue University, but unfortunately Professor Waldo is no longer with us.

          • Pedro J. says:

            “I’m reminded of the bill put before the Illinois legislature in 1897 which sought to have the value of pi set equal to 3.2.”

            Not a good example. In this case we are talking about risk management based on the best science we have on the consequences of a temperature increase >1.5ºC. For a good recent review see

            Differential climate impacts for policy-relevant limits to
            global warming: the case of 1.5 and 2ºC. Earth Syst. Dynam., 7, 327-351, 2016

            Also you can realize the difference a 0.5ºC increase makes. People tend not to realize this is the average temperature increase which means quite a lot of energy on the climatic system. Just think in how much energy has been accumulated in the ocean before this increase can take place.

          • Pedro, take an actual look at the paper you cite. For example: even their computer models show global crop yields will be essentially the same whether we warm up 1.5ºC or 2ºC. The press release hyped the supposed decline (by the end of the century) in TROPICAL yields, but the actual paper acknowledges that on a global level yields will bare budge.

            The rest of the catastrophes are cherry-picks. Why do they only talk about water access in the Mediterranean, for instance?

            Take a look at the chart I posted. Take a look at the bets I mentioned. These are global numbers from now till we’re dead, not cherry-picks. If you disagree with my statements, surely you won’t have problem betting.

          • Pedro J. says:

            “Pedro, take an actual look at the paper you cite. For example: even their computer models show global crop yields will be essentially the same whether we warm up 1.5ºC or 2ºC. The press release hyped the supposed decline (by the end of the century) in TROPICAL yields, but the actual paper acknowledges that on a global level yields will bare budge.

            The rest of the catastrophes are cherry-picks. Why do they only talk about water access in the Mediterranean, for instance?”

            Let me cite what the abstract actually says (no more, no less)

            “Regional reduction in median water availability for the Mediterranean is found to nearly double from 9 % to 17 % between 1.5C and 2C, and the projected lengthening of regional dry spells increases from 7 to 11 %. Projections for agricultural yields differ between crop types as well as world regions. While some (in particular high-latitude) regions may benefit, tropical regions like West Africa, South-East Asia, as well as Central and northern South America are projected to face substantial local yield reductions, particularly for wheat and maize.”

            “Take a look at the chart I posted. Take a look at the bets I mentioned. These are global numbers from now till we’re dead, not cherry-picks.”

   was cited by you

            was not

            sure you don’t pick cherries 😉

  5. James Arathoon says:

    It is worthwhile pointing out that this 2050 80% CO2 reduction figure on 1990 emission levels takes no account of UK population growth (or much less likely population decline).

    Once you allow for population growth the target reductions on a per capita basis will be nearer to 86% than 80%. High end population growth will be 400,000 per year to 2050 which will be an extra 13.6 million people than today. Current population is around 65 million. 1990 UK population was around 57 million. Therefore high end 2050 estimate is 21.7 million more people resident in the UK in 2050 than lived here in 1990: a 38% increase over this 60 year interval.

    Lets assume 1990 emissions were 10 tonnes per capita in the UK. If the population was unchanged the allowed emissions would be 2 tonnes per capita, an 80% decrease. However if there are approximately 22 million more people resident in the UK compared with 1990 then each person can only emit 1.4 tonnes. which is roughly an 86% decrease calculated on a per capita basis.

    Given the law of diminishing returns in engineering investment, that is the non-linear increase in costs likely to be seen in trying to meet every additional percentage decrease in per capita emissions.

    The politicians have already shown us how little they understand about engineering and how much money can be wasted on technically immature green bling without hardly impacting on CO2 emissions at all.

  6. These are all very good points. Since you scrutinised it to this extent, what do you think is the absorption on DECC into the broader industry and trade ministerial portfolio? Thanks again!

  7. Douglas Brodie says:

    The CCC’s fifth carbon budget report came out in November 2015. Paul Homewood has published several posts to debunk it, see

    The summary of his 6th December post is:

    “Regardless of the outcome in Paris, the Government should immediately reject this Fifth Carbon Budget out of hand. Furthermore, it should also reduce the targets in the Fourth Carbon Budget to bring into line with a 40% cut in emissions from 1990 levels, as opposed to 50%.

    This will bring us back into line with the rest of the EU.

    Unless the rest of the world is prepared to make the same drastic cuts, we should also dismantle, or at least suspend, the Climate Change Act.

    Finally, it should either wind up the CCC, or defund it. If they want to pay, say, £5000 a year for someone to write crappy reports, I’ll volunteer now. At least it would allow Mr Gummer to devote more time to his business interests, which still include Chairman of Sancroft International (consultants in corporate responsibility and environmental, social, ethical and planning issues), Director of Veolia Voda (continental water company) and Non-executive Chairman, Valpak Holdings Limited and Valpak Limited (leading provider of environmental compliance, recycling and sustainability solutions).”

    Paul Homewood has also done a debunking of the recent CCC report on the 2017 UK climate change risk assessment, see

    He concludes:

    “The overriding conclusion is that the CCC have produced a deliberately scaremongering report, based on very little evidence and a huge amount of modelling.

    In particular, they have failed to provide any evidence that the small amount of warming seen in the UK has had any deleterious effect at all.”

    • Douglas Brodie says:

      I omitted to add that the conclusions of this post and those of Paul Homewood show yet again that the so-called “climate change consensus” is a fiction sustained only by an unbelievable establishment narrative of political assertions and propaganda from “follow the money” so-called experts.

  8. Peter Lang says:

    David Ellard,

    I’d be interested in a post on this matter. What I’d really like is a post with a chart plotting carbon tied up in biosphere over geologic time and versus CO2 concentration and global average temperature to support this statement.

    Life thrives in warm periods and struggles in cold periods. One line of evidence is there is more carbon tied up in the biosphere and less continental aridity during warm times (IPCC AR4 WG1).

    “Lower continental aridity during the Mid-Pliocene”

    10% – 33% less terrestrial carbon storage at the LGM compared to today (300-1000 GtC less C in biosphere at GCM compared with preindustrial 300 GtC)

    Scottese Paleomap project has interesting charts on global average temperature for the past 540 million years, average temperature of the tropics over that period and temperature gradient tropics to poles and average temperature at the poles versus global average temperature. It seems there is no evidence to support the contention that 3 C warming is a threat. To see these charts, the reference and my comments see here:

    • Pedro J. says:

      “Life thrives in warm periods and struggles in cold periods.”

      The point is not about life. It is all about civilization. It is seashores levels (a few billion people live over there), food growth, etc. See positives and negatives of global warming

      “It seems there is no evidence to support the contention that 3 C warming is a threat”

      “there is no evidence” means not the same that “there is not certainty”. Science is all about control of uncertainty. Of course 3ºC is within the uncertainty interval for the threshold for a complete ice-free Greenland, for example. And look to the last papers about PETM. The mean post-1750 temperature rise rate (approximately ~0.0034°C/year, or ~0.008°C/year where temperature is not masked by sulphur aerosols) exceed those of the PETM (approximately ~0.0008 – 0.0015°C/year) by an order of magnitude and mean glacial termination warming rates (Last Glacial Termination [LGT] ~ 0.00039; Eemian ~0.0004°C/year) by near to an order of magnitude. Nothing to be worry about.

  9. john PITMAN says:

    There is increasing evidence that there is an important synergistic interaction between the ‘fertilization’ effect of increasing atmospheric CO2 and the parallel increase in reactive nitrogen Nr as a result of and increase in nitrogen deposition rates globally since the 1970s.

    Both modelling – see Bala et al 2013
    Nitrogen deposition: how important is it for global terrestrial
    carbon uptake?

    and direct measurements of the inks between carbon sequestration and nitrogen deposition in Boreal forest e,g, northern Sweden:
    Sponseller, R A., Gundale, M J., Futter, M., Ring, E., Nordin, A. et al. (2016)
    Nitrogen dynamics in managed boreal forests: Recent advances and future research directions.
    Ambio, 45: S175-S187
    both show that much of the ‘extra’ biomass increments are taking place in Boreal forest, which are the most responsive to warming.

    Of course, the only trouble is that the same areas are also seeing the huge Holocene peats and other organic soils, reserved until recently by the permafrost, are now thawing, which is in turn associated with an increase in methane hydrate volatilization. See

    Zona et al 2016 Cold season emissions dominate the Arctic tundra methane budget

    So it is all about feed-back loops, in the C/N cycle, especially in the colder predominantly northern hemisphere regions.

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