I started on this yesterday, had to put it aside for work, and I’m hugely busy today. Then I thought, you know, I have a whole army of people that can crowdsource an article, so why not ask them to help?
OK the premise starts with this press release:
Higher temperatures to slow Asian rice production
Production of rice will be thwarted as temperatures increase in rice-growing areas with continued climate change
Production of rice—the world’s most important crop for ensuring food security and addressing poverty—will be thwarted as temperatures increase in rice-growing areas with continued climate change, according to a new study by an international team of scientists.
The research team found evidence that the net impact of projected temperature increases will be to slow the growth of rice production in Asia. Rising temperatures during the past 25 years have already cut the yield growth rate by 10-20 percent in several locations.
Published in the online early edition the week of Aug. 9, 2010 in Proceedings of the National Academy of Sciences —a peer-reviewed, scientific journal from the United States—the report analyzed six years of data from 227 irrigated rice farms in six major rice-growing countries in Asia, which produces more than 90 percent of the world’s rice.
“We found that as the daily minimum temperature increases, or as nights get hotter, rice yields drop,” said Jarrod Welch, lead author of the report and graduate student of economics at the University of California, San Diego.
…
more here:
http://www.eurekalert.org/pub_releases/2010-08/uoc–htt080610.php
Problem is, I don’t quite believe this study, especially since the INTERNATIONAL RICE RESEARCH INSTITUTE shows this graph:
Average rice yield in the Philippines and a selection of
other rice-growing countries (tons per hectare) (Source: FAOstats)
Source: http://beta.irri.org/test/j15/index.php?option=com_content&view=article&id=393&Itemid=100104
I don’t know a thing about rice growing, but I figure some readers do. How can we have a temperature rise and CO2 rise in the past century and have 50 year increasing rice yields in the same Asian countries as the study?
Some other data:
http://asiapacific.anu.edu.au/newmandala/2009/09/10/more-on-thailands-low-agricultural-productivity/
http://beta.irri.org/test/j15/index.php?option=com_content&view=article&id=710&Itemid=100111
I can compile what readers find and post in comments and present it as a new article. Thanks for your consideration – Anthony
Higher overnight temps could be caused by higher humidity, which would also cause more fog and clouds, which reduce available light and should reduce growth.
Maybe the rice farmers just want to make more money per planted acre of land.
Happy Birthday, Willis!!!
PS – Moderator: I think Milwaukee Bob left a hanging italic command.
PPS – What does “PNAS” stand for anyway? Post-Normal Alarmist Sciencism?
DirkH says:
August 10, 2010 at 10:32 am
LOL!
Let me try.
“There is less more rice!”
I don’t know if they saw that rice does not grow well outside the tropics or places with hot micro-climates.
Since the hockey stick graph was forged, there are no correlation between rice growth and that graph.
Hmmm!
So a warming world over fifty years increases rice yields as a matter of concrete fact yet the alarmists claim that rising temperature would have the opposite effect to that shown by the actual records?
Falling temperatures may have that effect but GM tech and agricultural innovation would cancel that out in a short time but the alarmists cannot admit that global temperatures are falling so they blame rising temperatures instead in an ill thought out rushed and bodged up joke of a report. Just one more mumbo jumbo pseudo science filler to stack with the rest of the thousands of rubbish papers and reports and studies and articles. The alarmists wanted a mountain of evidence, so they made that mountain out of rubbish and it shows.
From CO2 Science. I couldn’t remember which “c” rice was.
Reference
Wand, S.J.E., Midgley, G.F., Jones, M.H. and Curtis, P.S. 1999. Responses of wild C4 and C3 grass (Poaceae) species to elevated atmospheric CO2 concentration: a meta-analytic test of current theories and perceptions. Global Change Biology 5: 723-741.
What was done
The authors conducted a massive review of the scientific literature published between 1980 and 1997 to compare the responses of wild C4 and C3 grasses to atmospheric CO2 enrichment.
What was learned
After analyzing approximately 40 and 80 individual responses of C4 and C3 grasses to elevated CO2, respectively, it was determined that both types of grasses respond favorably to atmospheric CO2 enrichment. Photosynthetic rates, for example, increased by an average of 25 and 33% for C4 and C3 grasses, respectively, in response to a doubling of the atmospheric CO2 concentration. In addition, atmospheric CO2 enrichment increased total biomass of C4 and C3 grasses by 33 and 44%, respectively. Thus, it is abundantly clear that C4 plants can (and do!) respond robustly to increases in the CO2 content of the air.
What it means
As the atmospheric CO2 concentration continues to rise, C4 plants will likely exhibit significant increases in photosynthesis and biomass production that will closely parallel those of C3 plants, which often have been implicated to respond much more favorably to elevated CO2 than do C4 plants. Consequently, this literature review suggests, and its authors state, that “it may be premature to predict that C4 grass species will lose their competitive advantage over C3 grass species in elevated CO2.” Thus, as the atmospheric CO2 content of the air continues to rise, it is highly unlikely that C3 plants will displace C4 species. Indeed, rising atmospheric CO2 concentrations should help to maintain biodiversity in ecosystems where C4 and C3 plants coexist.
Reviewed 1 November 1999
Printer Friendly VersionCopyright © 2010. Center for the Study of Carbon Dioxide and Global Change. All Rights Reserved.
Well we knew we were all going to die — If anything, would it be better to talk about what the cold has done to California food crops? And the southern hemisphere’s disastrous winter? The pathetic ‘studies pro-global warming for government grants’ is getting really old.
“The fruits and vegetables, the tomatoes and a lot of the citrus and things like raspberries are not ripening up because it’s not getting hot long enough,” she said, adding that some fruit could taste less sweet because less sun means less sugar content.
Read more: Temperatures continue well below average in Southern California – Whittier Daily News http://www.whittierdailynews.com/news/ci_15723011#ixzz0dkRKzqjK
This link is to a ppt. presentation from the United Nations Framework Convention on Climate Change (UNFCCC), discussing rice production in the Philippines:
http://unfccc.int/search/search?q=rice+production&btnG=Search&entqr=0&output=xml_no_dtd&sort=date%3AD%3AL%3Ad1&ud=1&client=unfccc_frontend&oe=UTF-8&ie=UTF-8&proxystylesheet=unfccc_frontend&site=default_collection
…looks like they are doing just fine to me!
More hokum and bunk from the CAGW crowd. They can’t even agree on what the future dire effects of AGW are likely to be!
Can you set one article into a wiki form? so we could all edit a single document? or at least those who are regulars and approved? It could prove a interesting experiment on how to make a blog page, once complete to your expectations just lock the page and publish.
Pre-blogging?
Pre article > Wiki > Group write > Publish.
In my opinion, there has been a great benefit to world crop yields from increased atmospheric CO2. In the last 50-60 years, along with ground water irrigation, CO2 has probably accounted for the lack of wide-spread famines predicted by various alarmists during that same period of time. But CO2 is the designated villian now and gets no credit in today’s populist environment.
PJP says: August 10, 2010 at 10:51 am
On the claims made. Without access to the article itself, it is a bit difficult to judge. However, I believe that the increases in rice production over the past 20 years or so have been due to:
* Better crop management techniques (education of farmers).
* Better pest/disease management.
* High-yield varieties of [r]ice.
* Increased cultivation area.
1. If this study includes the 2007-2009 growing seasons when world nitrogen prices spiked, then it’s bs. Poorer countries reduced nitrogen use.
2. Increased cultivation area reduces yield. The best land is always in cash crop production. Marginal, lower yielding pasture land may or may not be.
3. The higher trend previously was associated with improved genetics. As you can imagine, further increases from traditional genetics are becoming more difficult.
4. Yields can still be greatly increased by better management practices in poor countries.
5. In this case, temperature anomalies are less than useless. It is the absolute temp that affects yield. So if the average nighttime temperature increases from 82-82 F, a whopping 2 F increase, rice doesn’t give a darn. If the average nighttime temp increases from 98.5-99F (hypothetical values), Houston we have a problem.
I will not attempt to comment on the authors complete absence of any plant physiology knowledge. Was this a master’s thesis?
Overall grade D-
http://unfccc.int/files/meetings/workshops/other_meetings/application/vnd.ms-powerpoint/tibig.ppt.
Sorry, this is the correct URL directly to afore-mentioned powerpoint. However, please review the reports & information posted throughout the UNFCCC website, I don’t see these quoted very often by either side of the AGW argument. Interesting stuff in here about manure methane/nitrous oxide production in the developing world for example.
“Rising temperatures during the past 25 years have already cut the yield growth rate by 10-20 percent in several locations.”
Increasing the total yield by the same amount every year will naturally lower the rate of increase. It doesn’t mean less rice each year.
Looks to me like a rogue paper from UCSD that is merely fulfilling its contractual funding obligations by mentioning temperature rise/global warming/CO2 in any paper that comes from there. Perhaps its course calender has a reference to temperature rise/global warming/CO2 to account for rising costs of tuition (Ka-ching), student fees (Ka-ching), parking (Ka-ching), and pensions for tenured professors (Ka-ching, ka-ching, ka-ching). 😉
@ur momisugly mkelly. Rice is c3 but they are inserting c4 genes into the rice because c4 plants are more drought resistant and therefore produce better crops with less water.
It’s true that 90% of plants are c3, however 40% of commercial crops are c4 (think maize and sugarcane). So we have an ever increasing yield of plants that fix 4 carbon atoms.
** Can anyone point me to the information, as to which atmospheric gases are decreasing in response to increased C02?
Quick summary for those skimming:
It’s not the YIELD that has supposedly been reduced, it’s the GROWTH RATE OF YIELD. In other words, yield is still increasing, just not by as much as before. And it took 25 years to get that 10% reduction in increase. Yes, I said reduction in increase.
I also noticed the other weasel words, about how rice is “the world’s most important crop for ensuring food security and addressing poverty”. Rice is actually NOT the world’s most important crop, however when you frame it with security and poverty then it can be.
From http://www.sagevfoods.com/MainPages/Rice101/Production.htm
It’s simple. There are “tipping points”. I don’t know where they are, or how they work, but rest assured they exist and we’re approaching one right now.
Any change in rice yields is going to be swamped in the great movement of rice to hybrid rice, from inbred rice.
http://en.wikipedia.org/wiki/Hybrid_rice
30-50% increased yields!
Nature blogs linked to a copy of the paper.
http://blogs.nature.com/news/thegreatbeyond/pnas.Rice%20Yields.pdf
As Somerset Maughan wrote , truth is in the detail . Scientists should be forbidden to publish any story and to make doom and gloom projections without giving the particulars , the tiny details of the groundwork . So without specifying to your audiance or to your readers how and where the details are to be found to enable a truthful verification , every academic publishment is factually useles and worthless.
Lies are always generalisations and are always lacking detail . If a scientific study meets the latter criteria , which is the case right here , the chances are 99 to 1 that we are dealing with a cheat and a fraud . Let the authors come out of the boondogs and show us that they are willing to share the basics of their insights with the real world and not with a club of zealots contantly repeating their classical singsong in so-called scientific papers . From agriculture I happen to know a tiny bit and what is surprising by the way : Above a certain number of plants the production per acre does not rise any more so there are other parameters than plant virility controlling agricultural production and by the way more carbondioxide will lead to better yields .
Temperature – measurements without knowing the other circumstances is fine for statistics , but are completely useless without knowing the other factors determining growth and well-being . The border with voodoo science is not too far away from here.
The article is behind a pay wall but the supplemental material is available here:
http://www.pnas.org/content/suppl/2010/07/27/1001222107.DCSupplemental/pnas.201001222SI.pdf
My questions would be how well does the minimum and maximum temperature trends reflect trends at each specific farm sites and wet year vs dry. Each weather station is used to correlate yields at 20+ farms. The lat longs of those stations might provide insight. Are the stations located in drier sites than the rice fields. How do the station’s data compare to micro-climate data?
Trends were extrapolated from just 2-5 years of data between 1994-1999, covering the biggest El Nino year. El Nino years bring droughts to these areas and that does not seem to be factored into this study. Additionally dry years exhibit greater increases in minimum temperatures relative to wet years. In a similar 2004 study mean minimum temperature increased by 1.33°C in the dry season and by 0.80°C in the wet season from 1979 to 2003 . http://www.pnas.org/content/101/27/9971.full
‘”Production of rice—the world’s most important crop for ensuring food security and addressing poverty”‘
…Why is ‘rice’ the ‘World’s’ most important crop for ensuring food security…
…oh yeah, and ‘addressing poverty’? …what ever that ‘really’ means?
…according to ‘Wikipedia’ Sugar Cane, Maze, and Wheat produce globally: 2,673 million metric tons of individual crops, while rice makes up only 605 million metric tons. Individually, Sugar Cane, Maze, and Wheat are the worlds top 3 agricultural products, in that order, with rice finishing fourth.
http://en.wikipedia.org/wiki/Agriculture
EurekAlert could at least ‘try’ to scare us more by talking about the current ‘Globull’ warming in Russia, and how the wheat crop is gone, and how were all gonna die!
It should be pointed out that rice does not grow well blow 75 deg F. Warming would make there be more land with the minimum temperature!
When we stop looking at the temperature anomaly and look at the raw data, most of the warming has been in the night temperatures and not in the day temperatures. It is not hotter during the day, it is simply less cool at night. How could this possibly hurt the rice growth, which would slow down with cooling at night?
If they are really talking about a decrease in the rate of the growth of yield, then we have simply begun to reach the limits of this biological system. Blaming this on global warming, particularly when we are not warming, begins to really look stupid.
There is so much work being done out there in which the researchers take global warming as a given and then interpret anything they see as happening due to something for which they do not measure. That is very simply NOT SCIENCE as it should be practiced. Every study should take full measure of ALL of the parameters which are involved – none should be assumed as a given, well maybe gravity, but no others.
They also ignore that increased warmth would mean MORE PLACES could grow rice. They are holding location constant. A silly thing to do. But since rice needs heat, and lots of it, the whole argument is broken anyway.
BTW, lots of increased yield is available via the System of Rice Intensification should we need it.
http://ciifad.cornell.edu/sri/
When the whole world is hotter than Chico in August we can worry about heat reducing total crop yields. About 120+ F is needed to be an issue. Think Phoenix…