From the University of Exeter and the “we’re going to need a bigger computer model” department.
Climate predictions should include impacts of CO2 on life
Climate change predictions are not taking account of the full range of possible effects of rising carbon dioxide levels, researchers say.
Scientists currently use models in which warming of 1.5°C coincides with carbon dioxide in the atmosphere of between 425 and 520 parts per million (ppm).
But analysis by the University of Exeter and the Met Office suggests that if the climate warms slower, 1.5°C warming could be delayed until CO2 reached higher levels – up to 765ppm if no other greenhouse gases played a part or their effects were counteracted by pollution particles in the atmosphere.
Increased CO2 affects crop yields, plant biodiversity and ocean acidification – and the researchers warn studies can underestimate such impacts by using too narrow a range of CO2 levels.
“As well as being a major cause of global warming, CO2 also affects life directly,” said Professor Richard Betts.
“Higher CO2 concentrations cause increased growth in many plant species. This causes a general ‘greening’ of vegetation, but also changes the makeup of ecosystems – some species do better than others. Slower-growing large tree species can lose out to faster-growing competitors.
“It can also reduce the effects of drought to some extent, because many plants use less water when CO2 is higher.
“Both of these factors can potentially enhance crop yields, possibly helping to offset some of the negative impacts of climate change – although even if that happens, the nutritional value of the crops can be reduced as a result of the extra CO2.
“Rising CO2 also causes ocean acidification which is damaging to corals and some species of plankton.
“There is now a huge scientific effort going into figuring out what the world will look like when global warming reaches 1.5°C. To get the full picture, we need to consider these other effects of CO2 as well as those of rising temperatures.”
There is uncertainty about how much the atmosphere will warm in response to particular greenhouse gases – a measure known as “climate sensitivity”.
The study concluded that a wide range of CO2 concentrations could accompany global warming of 1.5°C or 2°C.
Explaining the new study, Professor Betts said he and Dr Doug McNeall did calculations by Intergovernmental Panel on Climate Change (IPCC) “in reverse”.
“Instead of calculating the probability of a particular amount of warming if CO2 doubles, we calculated the probability of a particular amount of CO2 rise for a particular level of warming (1.5°C and 2°C),” he said.
“This lets us estimate what the range of CO2 concentrations would be when global warming passes those levels, if CO2 were the only thing in the atmosphere that we are changing.”
###
The paper, published in the journal Nature Climate Change, is entitled: “How much CO2 at 1.5°C and 2°C?”
https://www.nature.com/articles/s41558-018-0199-5
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The only thing this paper does is try to cover every possibility, then later they will say, we did it. There is no science in it. And they are back tracking.
They just can’t accept any possible benefits from higher atmospheric CO2, can they? Every effect of CO2 and warming must be “bad”. There has to be a “but”:
“Higher CO2 concentrations cause increased growth in many plant species. This causes a general ‘greening’ of vegetation, BUT also changes the makeup of ecosystems – some species do better than others. Slower-growing large tree species can lose out to faster-growing competitors”
“It can also reduce the effects of drought to some extent, because many plants use less water when CO2 is higher. Both of these factors can potentially enhance crop yields, possibly helping to offset some of the negative impacts of climate change – ALTHOUGH even if that happens, the nutritional value of the crops can be reduced as a result of the extra CO2″
I suppose it’s progress, of a sort, that they can even say these things. Small mercies.
Oh my, the backpedaling is getting serious now. But now they have a problem. They are trying to be two things at once; serious scientists as well as pseudoscientists. The two things just don’t work very well together. Oh well, maybe they’ll get there eventually.
Increasing CO2 is ‘Greening’ the planet?
Cool! It’s ‘virtue signaling’, on a planetary wide scale!
Yet there are still a lot of warmists who deny that CO2 is capable of greening the planet.
” From 2000 through 2016, CO2 emissions to the atmosphere from burning of fossil fuels rose from 6.7 PgC yr-1 to 9.9 PgC yr-1 (1 petagram of carbon is 1015 gC, or 1 billion metric tons C, or 3.67 billion metric tons CO2). ” http://www.esrl.noaa.gov/gmd/ccgg/carbontracker
That amount is way too low when in all of the scientific literature it was increasing by 1 BMT year over year during that time. It takes by chemistry a release of 12 BMT to add 1 ppm/v to the atmosphere. The sink is about 6 BMT and the atmosphere takes in another 6 BMT. “Climate Science” can’t have it both ways. Using a lower number to justify current co2 rates ppm/v per year. Then if there are lower amounts of production, then we had higher rates of production back in the 1960’s and 1970’s. Calculating the rate of co2 production based on the rise in atmospheric is biased. It’s the same biases that they used to determine the relative warmth and coldness, lack of either during the MWP and LIA.
The only good number I have for co2 production is 12 BMT ( given in Metric Tons). Which if you look at the record for 1965, co2 rose about 1.08 ppm/v. Which I think is about right The atmospheric co2 level was about 318 at the time.
Both NOAA and the EUEC both claimed in March of 2015 that co2 production had leveled off at 38 BMT +/- a few… If it took 18 years for co2 ppm/v to reach 3 ppm/v per year from 1998, what caused the spike in co2 for 1998? Either we are producing way less co2 than reported, AGW is making numbers up, or they don’t know. 3.67 BMT is less than 1 ppm/v per year… That would explain why all those years in the 2000’s were below 2 ppm/v per year rise. And it would explain why temperatures have not gone up. But that’s not case. We can follow the audit trail of how much fossil fuels have been mined. We can look at any graph to see how much China and India have increased co2 production.
In any scientific field, there are amateurs, semi professionals, and professionals. There is also a wide array of people who have the basics. I’m not a amateur astronomer, but I have enough of the basics that I can explain why the earth is not flat to someone raised in a foreign country that believes that. I can agree with the basics because it works.
If AGW could convince me that the world is in imminent danger, I could convince anyone. Changing numbers doesn’t help. You can’t do basic research if the numbers are deliberately being changed. In fact it looks like fraud. The periodic table in chemistry hasn’t changed since it’s inception. ( other than adding additional elements) Gravity is still measured at 9.8 m/s^2. In electricity, nothing has changed. The laws and formulas allow us to communicate almost instantly over vast distance, with greater understanding and application.
Where are we in the graph of how much the temperature should have risen given the amount of co2 that is in the atmosphere. I can tell you. Doubling the co2 should double the temperature of the calculated amount of 15 C that is ambient at 280 ppm/v. Given that the co2 level has risen to 411 ppm/v that is 46% of the needed doubling, or the temperature should be 7 C warmer than when the co2 level was 280 ppm/v. Is there any data that shows a 7 C in world temperatures? Is there any data that shows half of that at 3.5 C? Is there any data that shows a 1.75 C increase in temperature? Will be? When? In 1965 the co2 level was 318 ppm/v, that is 13% increase in co2. That is a 2 C rise in temperature should already be since 1965.
I can not agree with AGW on any level.
why would you say that doubling CO2 would double temperature?
AGW has used co2 as the greenhouse gas that raises temperature. The blackbody is calculated at 255 K and the the greenhouse effect raises it another 33 K to 288 K ( that was the observed world temperature) … or 15 C or 59 F…. according to the IPCC doubling the co2 from 280 to 560 ppm/v will raise the temperature an additional 15 C to 303 K or 30 C . From that you can graph the rise in co2 with the associated rise in temperature. In 1965, co2 was 318 ppm/v, it should already be 2 C warmer on a consistent basis. 318 ppm/v is a 13% rise in co2 above 280 ppm/v. Currently at 411 ppm/v, the temperature should be approaching 7 C warmer or a consistent 20 – 22 C. Instead we’ve got, well not much, 15.18 C
If it were doing that, there would be mass migration away from areas near the oceans. I’d be moving too.
The formula is derived from 1370 w/m^2 at top of atmosphere. at the surface, ((1370 x (1-a))/4 = 239.7 w/m^2. ( ‘a ‘ is albedo 30%) .. Which goes into the blackbody formula
(239.7)/(5.67 x 10^-8) and the 4th root of that =255 K .
I just realized something, I’ve done this math so often, sometimes you loose sight of something .
Then double co2 to find temperature AGW uses the formula
(239.7+239.7)/ (5.67 x 10^-8) 4th root = 303 K , a pretty toasty world temp of 30 C .
That’s why AGW is up in alarm about it. I’d be too if it were real.
This isn’t my math…. if you see something in this that looks strange… let me know. Or anybody….
‘From the University of Exeter and the “we’re going to need a bigger computer model” department.’
I like the Jaws reference.
100% renewables are impossible. The best that can be done is a world with 95 % (nuclear power plants, hydro power plants and geothermal power plants) with another 5% of fossil fuels. If this is what the greenies want, then I say take off the subsidies, relax the nuclear regulations and environmental regulations against dams and forget about this silly idea of CO2 being a pollutant, and may the best energy win. If the greenies refuse more nuclear power; then the present level of fossil fuels use wont drop to any less than 75%.
Can someone explain the ocean pH change function to me? Cartoon level is OK.
One is a warmer ocean doesn’t hold as much co2 becoming less acidic. Two, partial pressure from increased co2 increases ocean acidic. Which came first? The warmer ocean or the increased co2? Which one has a greater role, partial pressure or a warmer ocean?
And now please welcome our gorilla in the room … the effect of CO2-enhanced plant growth on extending the hydrological cycle into formerly arid areas and cooling the climate. Just recall how precipitously global temperatures fell during the Carboniferous for precisely this reason. The humid soils deposited by the great Cryogenian and Sturtian glaciations before the Cambrian, were colonised by plants and trees as the earth’s arid continents became gardens and forests. At that time CO2 also fell as the increased vegetation photosynthesised it into wood and coal.
Climagesterium party line is that the falling CO2 in the Carboniferous caused the cooling but this puts the cart before the horse and ignores the de-aridifying effect of expanding plant growth. They make the same mistake again in missing the fact that the current CO2 enhanced plant growth and extent will do the same again as it did in the Carboniferous and always does – CO2 exerts a cooling effect via plant transpiration.