From the LONDON SCHOOL OF HYGIENE & TROPICAL MEDICINE, doom division, comes this story that seems not to realize what every gardener knows: that many vegetable plants do better in a warmer environment with more CO2, hence the idea of “hothouse tomatoes.
What’s funny is that their own paper reported this:
The mean (95% CI) reported yield changes for all vegetables and legumes combined were +22.0% (+11.6% to +32.5%) for a 250-ppm increase in CO2 concentration…
… −8.9% (−15.6% to −2.2%) for a 25% increase in O3 concentration,−34.7% (−44.6% to −24.9%) for a 50% reduction in water availability, and −2.3% (−3.7% to −0.9%) for a 25% increase in salinity.
So, they are assuming water availability will be less and more salty in the future, and there will be more ozone O3 pollution. Yet all indications thus far that a warmer world will be a wetter world due to enhanced atmospheric water vapor, and so far, ozone pollution has been declining, especially in coastal areas.
Then there’s this:
The authors acknowledge limitations of the study, including the fact that collated evidence on the impact of environmental changes on the nutritional quality of vegetables and legumes was limited and the research team identified this as an area requiring more evidence generation.
Predicted environmental changes could significantly reduce global production of vegetables
Prioritizing access to new crop varieties and improved agricultural practices is crucial to minimizing the potential negative effects of climate change on health, say researchers
The study, led by the London School of Hygiene & Tropical Medicine (LSHTM), is the first systematically to examine the extent to which projected changes such as increases in temperature and reduced water availability could affect the production and nutritional quality of common crops such as tomatoes, leafy vegetables and pulses.
If no action is taken to reduce the negative impacts on agricultural yields, the researchers estimate that the environmental changes predicted to occur by mid- to end-century in water availability and ozone concentrations would reduce average yields of vegetables and legumes by 35% and 9% respectively. In hot settings such as Southern Europe and large parts of Africa and South Asia, increased air temperatures would reduce average vegetable yields by an estimated 31%.
Environmental changes, including climate change, water scarcity and biodiversity loss, are predicted to become more profound in the 21st century – posing significant challenges to global agriculture, food security and nutrition. While there is growing evidence that predicted future changes in temperature and rainfall will lead to significant reductions in the yields of many staple crops such as rice and wheat, the impacts on vegetables and legumes – important constituents of healthy diets -are largely unknown.
To address this evidence gap the researchers conducted a systematic review of all the available evidence from experimental studies published since 1975 on the impacts of changes in environmental exposures on the yield and nutritional quality of vegetables and legumes. Experiments included in the review were conducted in 40 countries.
The team then estimated the effects on the yields and nutritional quality of crops of changes in key environmental exposures, including increases in greenhouse gases (tropospheric carbon dioxide and ozone), reduced water availability for irrigation and rising ambient temperatures.
Previous research has shown that raised levels of carbon dioxide would increase crop yields, but this study identified for the first time that these potential yield benefits are likely to be cancelled out in the presence of simultaneous changes in other environmental exposures.
The researchers warn that in the absence of substantial efforts to respond to predicted future environmental changes, reductions in the yields of vegetables and legumes will substantially alter their availability globally. Such changes may affect the affordability and consumption of vegetables and legumes in the mid- to long-term and this could have significant impacts on population health all around the world.
Dr Pauline Scheelbeek, lead author at LSHTM, said: “Our study shows that environmental changes such as increased temperature and water scarcity may pose a real threat to global agricultural production, with likely further impacts on food security and population health.
“Vegetables and legumes are vital components of a healthy, balanced and sustainable diet and nutritional guidelines consistently advise people to incorporate more vegetables and legumes into their diet. Our new analysis suggests, however, that this advice conflicts with the potential impacts of environmental changes that will decrease the availability of these important crops unless action is taken.”
To mitigate the risks that future environmental changes pose to these crops, researchers say that innovations to improve agricultural production must be a priority, including the development of new crop varieties as well as enhanced agricultural management and mechanisation.
Professor Alan Dangour, senior author at LSHTM, said: “We have brought together all the available evidence on the impact of environmental change on yields and quality of vegetables and legumes for the first time.
“Our analysis suggests that if we take a ‘business as usual’ approach, environmental changes will substantially reduce the global availability of these important foods. Urgent action needs to be taken, including working to support the agriculture sector to increase its resilience to environmental changes and this must be a priority for governments across the world.
“But our study also identifies the broader policy relevance of environmental change. Vegetables and legumes are essential constituents of healthy diets and so efforts to ensure that their global availability is not threatened by predicted environmental changes must also be high on the global public health agenda.”
The authors acknowledge limitations of the study, including the fact that collated evidence on the impact of environmental changes on the nutritional quality of vegetables and legumes was limited and the research team identified this as an area requiring more evidence generation.
The study was funded by the Wellcome Trust as part of its Our Planet, Our Health programme.
Dr Howie Frumkin, Head of Our Planet, Our Health at Wellcome, said: “Improvements in agricultural technology have dramatically boosted the world’s food production over the last 80 or so years. But we mustn’t be complacent. Environmental changes, including more chaotic weather patterns and a warming climate, threaten our ability to feed the world’s people.
“This excellent review highlights that some of the most important foods, and some of the world’s most vulnerable people, are at highest risk. This research is a wake-up call, underlining the urgency of tackling climate change and of improving agricultural practices.”
###
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
This is what happens when you let a bunch of sissified, feminized bed wetters, no offense to strong conservative women intended, teach and do research at supposed institutions of higher education. Do they let these folks go outside alone? Evidently these “researchers” have never grown a garden. Is there anything for which co2 is not harmful?
…Previous research has shown that raised levels of carbon dioxide would increase crop yields, but this study identified for the first time that these potential yield benefits are likely to be cancelled out in the presence of simultaneous changes in other environmental exposures….
I’ll go along with that finding. My models of future farm production under environmental conditions show the following findings:
1 – growing capability for produce: +150%
2 – ability to plan growing season using IPCC weather models: – 30%
3 – ability to sow and harvest crop using photo-electric equipment: -50%
4 – ability get produce to market using environmentally-friendly transport: – 80%
So yes, I predict a considerable fall in global vegetable production….
Now my Head hurts.
Those charlatans don’t care about data, logic and science. Their aim is to publish a junk paper, that could be cited later by the Goebels Warming zealots, the IPCC included, as “climate science has demonstrated that warm means less vegetables production”. The sole purpose is to sustain the propaganda machine and to keep the fundings gravy train rolling. Mission accomplished.
Four degrees C is at the top end of global average temperature, as estimated by climate models, which are running hot compared to historical temperatures. If these predictions are based on hot-house experiments, it isn’t stated whether the temperatures were averages, peak temperatures, or average daily highs. Without that information, it is difficult to assess the danger. In any event, the temperature change in the last 100 years has been about 1 deg C, with most of that before 1950. Furthermore, the change in the global average has been mostly in the night-time and Winter Temperatures. Lastly, it is commonly acknowledged that the Arctic is warming about twice as fast as the global average. That means, the temperatures in the corn belt will not increase as fast as the global average. Overall, this appears to be a worst-case scenario with little supporting statistics on the uncertainty of the assumptions or conclusions.
How is it that a researcher in atmospheric sciences is making claims best made by agricultural scientists and international economists?
Now, water is another story! But, much of the concern is about depletion of aquifers utilized for irrigation, and is largely unrelated to climate.
Dinner At The Climate Change Family home…..
Climate Change Dad: “Where are the vegetables?”
Climate Change Mom: “They’re not home from school yet.”
Agronomy time: elevated CO2 (“eCO2”) -> more fine roots -> more turnover into soil carbon -> more soil microbes. Under just eCO2 conditions extra microbes reduces N for plants while mobilizing more P for plants. Water (soil moisture) excess -> more N availability lost than P & more P solubility for plants. eCO2 reduces plant transpiration & sustains soil moisture. Raising soil moisture & also CO2 creates greater microbial immobilization of N & plants’ ratio of P goes up. Well, temperature elevation (“e°T”) accelerates microbial activity/turnover allowing more N available to plants. But, if soil drying problematic under e°T then P availability reduced & the ratio of N to P goes up. Different plants deal with the availability of N in respect to availability of P with different outcomes & in field grown crops the N:P ratio is impacted by eCO2, e°T (if present), water & soil characteristics. Plant protein synthesis is demonstrated repeatedly to be impacted by eCO2 by varying degrees – a feature is N:P ratio.
I wish alarmists would make up their minds whether a warmer world is wetter or drier than a cooler one. Whichever can be made the scarier, I guess, is the criterion.
But without an assumed water vapor feedback, the ECS of doubling CO2 is only 1.2 degrees C, so the models at least have to go with wetter.
Felix,
Actually, precipitation seems to be an even bigger problem with GCMs than temperatures because different models often get very different precipitation forecasts for the same regions.
I went to sleep in the middle of trying to read that drivel.
“urgent action needs to be taken” – okay, but what? Shutting off your supply of donuts and coffee? Making you science guys get real jobs and do your own cooking? Grow a garden?
Man! Theses people are so lost in their need to be important that they bore the living daylights out of me. Cut off their funds, will you? that will solve the problem, quickly.
I can hear the howling now: “What?!? No more money for producing poppycock papers? How could they!! We’re imporrant!! Important, I tell you !!”
These twits have tried to stir up a tempest in a sauteeing pan and have failed. Vitamins can replace lost nutrients, as can other means of providing foodstuffs in an emergency. They make it sound as if Doomdsay is around the next corner, when it isn’t.
Cut off their funding!!! Please!!! All they do is waste time and money and produce nothing of any value.
Sara
the secret is, as I have discovered, not to read anything but the headline. Then skip down to the comments. Much more informative and far more fun.
And I suspect the fund cutting is coming once the Donald revs up the US economy and slaps down the EPA.
With any luck, that means when America sneezes, Britain catches a cold, and we’ll soon be rid of our green brigands en mass.
HotScot, I do hope that you are right.
Grant money is supposed to produce something beneficial like a new vaccine or a better, more cost-effective light bulb. What these people do is waste money that could go for something useful.
A minimum of homework would show this :
http://wellcomelibrary.org/collections/digital-collections/makers-of-modern-genetics/digitised-archives/eugenics-society/
Not for weak nerved, not for “just the fact’s ma’m” dumbed-down Kan’t-ian “scientists”.
Wow! Fact checking not sheer laziness. Have to say though, the new Google search rules are making this harder to find – the lazy have to fight the 250,000-legged dog called Map-Reduce (googles bloodhound) – but as Alice said, a dog at any scale is dog, rather a poodle.
So use Google-Poodle but remember Alice’s keen observation!
been so damned cold here in Maine (still have 39-40 deg F mornings) MANY gardens having problems getting stuff to grow.
The summary provided did not explain why they assumed a 4 degree temperature increase, a 25% increase in O3, a drop in available water, or how they arrived at a salinity increase. The paper itself does not appear to be readily accessible, but their supplemental info is:
http://www.pnas.org/content/pnas/suppl/2018/06/06/1800442115.DCSupplemental/pnas.1800442115.sapp.pdf
A chart on page 14 of the supplemental info (I tried unsuccessfully to paste it here…perhaps someone clever at posting pix can do that), shows where they got their numbers from. It’s truly a joke and it’s hard to believe this was published.
The statement in the abstract, that the study was based on “environmental changes predicted to occur,” appears to be entirely untrue. They took a bunch of studies that experimented using various factors (summarized in column D1 in the chart) to see what impact such factors had on different “vegetables and legumes”. Those studies did not themselves attempt to project / predict future climate.
However, they combined those experimental numbers with some IPCC projections to establish the “standardised change” used for their paper. That means the numbers used are entirely and completely fictional, divorced from any attempt at a real projection of future climate between now and 2100…and that’s being generous since the IPCC projections themselves are fictional. The standardized changes used in the paper do not, in any sense of the concept, amount to “environmental changes predicted to happen”.
So…if there is a 4 degree C temperature increase by 2100 (above the IPCC range, which itself is suspect), water availability drops by 50%, and all those various other factors also come into play (how that will happen is unclear and not projected to occur by the IPCC), then bad things might happen.
If anyone has access to the full paper, is there some form of discussion justifying their numbers, beyond the obvious – i.e., if we make it bad enough, we’ll get headlines?
This paper seems utterly pointless…
In the future, CO2 will cause it to rain saltwater.
I’m guessing that they believe CO2 can convert to ozone if they wish hard enough for it.
Future headline: “CO2 induced global food glut causing uptick in population, wellness. Could eventually cause famine, war, malaria, itchy feet…”
Can’t wait till CO2 reaches 500, good bye deserts, famines, itchy feet….
Some of the C3 plants whose bounty will be increased by CO2 enrichment of our air:
Most small seeded cereal crops such as rice (Oryza sativa), wheat (Triticum spp.), barley (Hordeum vulgare), rye (Secale cereale), and oat (Avena sativa).
Most trees and lawn grasses such as rye, fescue and Kentucky bluegrass.
Soybean (Gycine max), peanut (Arachis hypogaea), cotton (Gossypium spp.), sugar beets (Beta vulgaris), tobacco (Nicotiana tabacum), spinach (Spinacea oleracea) and potato (Solanum tuberosum).
Evergreen trees and shrubs of the tropics, subtropics and the Mediterranean; temperate evergreen conifers like the Scotch pine (Pinus sylvestris); deciduous trees and shrubs of the temperate regions, e.g. European beech (Fagus sylvatica), as well as weedy plants like the water hyacinth (Eichornia crassipes), lambsquarters (Chenopodium album), bindweed (Convolvolus arvensis) and wild oat (Avena fatua).
Oh, no! More weeds and tobacco (plus marijuana and probably poppy and coca)! We are doomed!
Farmers already fight to control weeds, so their greater potential growth is no threat.
“”… This advice conflicts with the potential impacts of environmental changes that will decrease the availability of these important crops unless action is taken….”.
A good LIA will do the same!
What’s with this “water scarcity” they seem to have thrown in or is this just another model driven exercise?
It’s not even as sophisticated as a “model-driven exercise”. They took the numbers used by the scientists conducting tests on plants (where, in some cases, the stressors included reduced water), and used essentially a middle point. See p. 14 of their supplemental information: http://www.pnas.org/content/pnas/suppl/2018/06/06/1800442115.DCSupplemental/pnas.1800442115.sapp.pdf
Ian
Bollox. Its just the new scare tactic.
A planet dominated by water, will soon run out of water.
So, where does it all go?
My family have been farming the same land for more than 800 years now. This gives us an historical perspective most governments and organizations cannot match. If you are a farmer, climate change is no laughing matter. Small changes in global temperature have vast impact on weather patterns. Please note that all agriculture is dependent on reasonably predictable weather. Farmers have to know when to plant and harvest their crops. If temperature or rainfall are abnormal, crops can fail and people starve. If you look at historical records from the Little Ice Age (roughly 1350 to 1850 AD) many countries lost 20% to 25% of their population. All this havoc was caused by a 2 degree drop in average temperature. This reduced average growing seasons by 1 to 2 months.
Increasing global temperatures cause even more problems. Rainfall becomes increasingly unpredictable and high temperatures decrease yields of most crops. For example, increasing temperature by 1 degree is the same as losing 4 inches of rainfall. 4 acre-inches of water can mean the difference between making a crop and having a parched field = no crop. If temperatures are 5 degrees Fahrenheit too warm when wheat is pollinating, yields can go down 30% or more. A few days difference in planting date can cut rice yields in half. Crops are very sensitive to small environmental changes.
Nobody said boo about global warming until some economist proposed a “carbon tax”. Then came the Great Climate Change Denier Campaign. Don’t play the ball, play the man. If there is no such thing as climate change, then we don’t need a carbon tax. Follow the money where it leads you. Or, if you don’t understand economics, read history. Climates do change and people do starve. Facts are stubborn things.
Eric Koperek, Plant Breeder
And this study passed peer review?
“Predicted environmental changes could significantly reduce global production of vegetables
Prioritizing access to new crop varieties and improved agricultural practices is crucial to minimizing the potential negative effects of climate change on health, say researchers
The study, led by the London School of Hygiene & Tropical Medicine (LSHTM), is the first systematically to examine the extent to which projected changes such as increases in temperature and reduced water availability could affect the production and nutritional quality of common crops such as tomatoes.”
_____________________________________________________
So London School of Hygiene & Tropical Medicine did a studie to show:
Cuisine of Montreal beats dining in New Orleans.
The Londoners should add Menu Cards to the abstract.
what an unmitigated pile of crap!
damned if theyre worth their present pay let alone ongoing employment
Everyone knows that vegetables grow best in <150ppm CO2 and under a kilometre of ice.