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
The Sahel is greening maybe due to increased CO2 levels http://news.nationalgeographic.com/news/2009/07/090731-green-sahara.html. The result is that they can increase rice growth. In West Africa’s Sahel region as a whole, production rose by 44% in 2008. For the 2009-2010 crop season, FAO is projecting double-digit growth in rice production for several countries. http://africarice.blogspot.com/ Sub-Saharan Africa can reduce its exposure to global rice market shocks by increasing regional production and by reducing dependence on rice imports. The fundamental trick in the article is that they never stated that today yield decreases. No they state: “Up to a point, higher day-time temperatures can increase rice yield, but future yield losses caused by higher night-time temperatures will likely outweigh any such gains because temperatures are rising faster at night,” said Welch. “And if day-time temperatures get too high, they too start to restrict rice yields, causing an additional loss in production.” Theoretically this is always true. As you keep heating up to a point it will start impacting crop negatively. Writing peer reviewed articles is easy this way. As long as you mention up to a point.
Just from memory, I seem to recall that China and other rice producing countries farming populations have been moving to the cities in large numbers over the past 10 years or so. That may have something to do with the slowing production as those farms are left vacant or given over to some other enterprise.
And before anyone runs off at the hip and claims it’s “the water” – Contrary to a common misconception, family rice farmers in California are among the best stewards of this precious resource. Only 16 gallons of water are needed to produce one serving of brown rice (25 gallons for white rice). That’s about the same as many other crops in the state, and about the same amount of water per acre as the average urban lawn.
Rice was once a thirstier crop, but a series of innovations over the last three decades has improved our water use efficiency. Newer varieties of plants are about half the height of older varieties, leading to more crop per drop of water. In addition, the use of clay soils helps conserve water, as does laser leveling of our fields.
Gota run…..
The yield is higher due to the ocean levels increasing with time due to temps and CO2. That has vastly increased the areal coverage of rice paddies at a pace much greater than the ability of temperatures and CO2 to decrease the yields through growing season changes.
Let me see if I understand. The yield per hectare has steadily increased due to better techniques, new strains, etc. But even though the yield is still increasing the rate of increase has slowed. And somehow global warming is to blame?
Isn’t it more likely that the large and/or easy improvements have all been implemented so the current improvements are minor? And aren’t new strains being constantly developed to deal with changing conditions?
Without their raw data it is hard to be certain. But based on the info we have, these ‘scientists’ should have there degrees recinded. Either that or they should be given a Nobel Peace Prize like algore. I mean assinine scare mongering (or the hope that you will actually accomplish something in the future) is a requirement for a Nobel Peace Prize these days isn’t it?
Yes, the slippery words here are “yield growth rate”, not raw yield. So they are saying that the rate of growth in yearly yield numbers are slowing down and this correlates with the fictitious increases in temperature we keep hearing about but never seem to experience. If we leave aside magic, and enter the realm of reality, many things will affect the “yield growth rate”, such as plant genetics, nutrient uptake rates from soil, bioavailability of nitrogen, and so on. For any given plant species we will eventually run out of things to tweak or modify, and the “yield growth rate” will plateau, (i.e. drop to zero). There will be simply nothing left to improve in the plant to make it yield any more given all of the factors that affect it’s rate of growth, availability of nutrients, input energy (sunlight), and so on.
Well, I don’t do “science by press release”, but if someone wants to email me the original article I’ll take a look … my naive view is that six years of data is far too short a time to get anything statistically significant, particularly the kind of second-order effect they are reporting, but what do I know, I was born yesterday.
willis
at
taunovobay.com
Having trouble getting this browser to post today!
There is a “real world condition” that explains the problem with rice yield in the Phillippines. It is called “The Fertilizer Scam”.
From here:
http://tatlongtala.blogspot.com/2006/03/senate-report-on-fertilizer-scam.html
Excerpt:
The Senate Committees on Agriculture and Food, and Accountability of Public Officers and Investigations (Blue Ribbon) have concluded that agricultural funds intended for farmers were diverted by Agriculture Undersecretary Jocelyn “Joc-joc” Bolante for the 2004 electoral campaign of President Gloria Arroyo.
Also:
The fertilizer fund appropriation was implemented only in 2004, incidentally during the election season. Funds were released from February to May 2004 or during harvest months when fertilizers are of no use because planting time starts in November. The DA’s Rice Program (known as GMA or Ginintuang Masaganang Ani) director Frisco Malabanan testified that fertilizer requirements for 2003 totaled
only P28.613 million for the entire Philippines – compared to the P2.806 billion released in 2004.
Also:
The fertilizers used were actually liquid fertilizers known as foliar, normally used for ornamental plants and flowers and anything leafy but not usually used for rice or corn. To add insult to injury, the “wrong and overpriced fertilizer for rice was even diluted with water.”
There’s bound to be lots of info on this at CO2science.org.
The first liunk to pop up on search for “rice”:
http://www.co2science.org//articles/V10/N46/B2.php
Reference
Krishnan, P., Swain, D.K., Bhaskar, B.C., Nayak, S.K. and Dash, R.N. 2007. Impact of elevated CO2 and temperature on rice yield and methods of adaptation as evaluated by crop simulation studies. Agriculture, Ecosystems and Environment 122: 233-242.
What was done
Two popular models of rice growth ORYZA1 (Kropff et al., 1994) and INFOCROP (Aggarwal et al., 2006) were calibrated for the indica rice variety IR 36 at ten different sites in eastern India and then used to predict rice yields for the ten sites for five 1°C incremental increases in temperature above typical ambient conditions, as well as for one 20-ppm and three 100-ppm incremental increases in atmospheric CO2 concentration culminating at a value of 700 ppm.
What was learned
The authors report that “for every 1°C increase in temperature, [the] ORYZA1 and INFOCROP rice models predicted average yield changes of -7.20 and -6.66%, respectively, at the current level of CO2 (380 ppm),” but that “increases in the CO2 concentration up to 700 ppm led to … average yield increases [our italics] of about 30.73% by ORYZA1 and 56.37% by INFOCROP,” which they “attributed to greater tillering and more grain-bearing panicles.” In addition, they note that the limitation on rice yields that is sometimes imposed by spikelet sterility at high temperatures can be “largely overcome by the selection of genotypes that possess a higher potential of spikelet fertility at high temperatures.”
What it means
In spite of the potential for enhanced global warming in the years and decades ahead – due to either anthropogenic- or non-anthropogenic-induced forcing – the world’s rice farmers should be able to meet the needs of the planet’s expanding human population … if (1) the air’s CO2 content continues to rise and (2) judicious use of plant breeding is made.
Big, big topic. In Indonesia gas producers are mandated to sell some of their gas to state owned fertilizer plants cheap. They give the farmers tons of cheap fertilizer, and the rice yields have climbed. The runoff has increased the algae in the South China Sea and many coral reefs near Java have died, not from heat, but from a coat of green scum. The total carbon budget-climate change picture of all this is a bit complex, but I’m sure our media can spin up an dire summary.
Mind you, refering to my pevious post, how is it that people think they are doing science when they run computer models? I would prefer that this article refered to actual real experiments. Others are available CO2science.org
“Rising temperatures during the past 25 years have already cut the yield growth rate by 10-20 percent in several locations.”
Ok, from Richard Black, BBC, we get:
“Yields have fallen by 10-20% over the last 25 years in some locations.”
http://www.bbc.co.uk/news/science-environment-10918591
Thank you, BBC, for not even being able to comprehend simple English sentences. Or not being able to use copy&paste. Or for deliberately spreading black propaganda. I guess that’s why he’s called Richard Black.
And thanks to Anthony for clearing this up by linking to the original press release. For a moment i thought Richard Black pointed out a real problem.
Rice yields may drop, but are expected to have the unexpected upside of increased rice krispie production. Unfortunately, since this would make life more pleasant and entertaining for children of all ages, rice paddies will have to be re-sown with hemp.
Rice is a C3 plant. The production of C3 plants slows conditions of high temperature and low concentration of atmospheric carbon dioxide (barley, sunflower, rice, tomato, wheat, peanut, cotton, beet, oats and most of trees). However, we are talking about temperature above 40 °C and mass fractions of the atmospheric CO2 below 300 ppmV, which has not been the case in Asia.
I think it is not a scientific paper, but a statistical comparison. The agricultural production in any country shown an accelerated growth since the introduction of modern technology and/or cheap manual labor; nevertheless, in developing countries, the agricultural growth has been limited by several factors. For example, many people emigrate from the countryside to the industrialized cities to be employed like manual workers in factories. Another factor is the limit of expansion over fertile lands, which has been comprised by excessively strict environmental legislations in every country. Another cause is the availability of resources, like irrigation, that is diverted toward factories and limited for the agricultural work. I think that most of the academies have taken parties and publish anything that implies the anthropogenic climatic change, either real or unreal.
The article’s conclusions depend on this presupposition. McKitrick and McIntyre (2010) show climate models over predict atmospheric temperatures by 200% to 400%. McKitrick (2010) further exposes serious Urban Heat Islands effects in the surface data. This contamination caused between 33% and 50% of the apparent recent increase in temperature.
An alternative projection of rice production could be obtained by evaluating the impact of Don Easterbrook’s temperature projections driven by the Pacific Decadal Oscillation (PDO).
CO2 Science reviews
Xiong, W., Conway, D., Lin, E. and Holman, I. 2009. Potential impacts of climate change and climate variability on China’s rice yield and production. Climate Research 40: 23-35.
These researchers come to the opposite conclusion, showing the major impact of CO2 fertilization and increased growing season:
Such models could then be validated using methodologies such as developed by
Demetris Koutsoyiannis et al. at ITIA.
e.g., Credibility of climate predictions revisited G. G. Anagnostopoulos, D. Koutsoyiannis, A. Efstratiadis, A. Christofides, and N. Mamassis European Geosciences Union General Assembly 2009
Vienna, Austria, 19‐24 April 2009
I would hazard a “guess” that there would be very marked differences in statistical uncertainties between such projections. i.e., such alternative models may well show strong benefits from increased CO2 with much lower temperature dependence.
We hear this clap trap called peak oil
We have also hear pertaining to crops that there is a point at which yields can’t be increased. Russia is saying it is dry and yields are down 40%. They were 40% lower than American yields to begin with. Yes Joe Romm, we are also setting crop yield records every year when they say the crops will fail and we will have permanent droughts.
DirkH says:
August 10, 2010 at 10:32 am
___________________________
I have filled out the BBC’s complaint form. If enough people do, perhaps some of the lies will stop.
These guys don’t read the news: Have they wonder what floods mean?…a LOT of rain, which is why rice is cultivated in the Monzon areas.
Think they are just trying to get their invitations for the next CCHCPJ (Climate Change carnal pleasures’ jamboree).
I tried to get the article, but as usual, its hidden behind a paywall.
I think this needs to be fixed. Any work which receives one cent of public finance, either directly or via the facilities used in its production should be available free of charge.
Yes, this would put the journals out of business, but I don’t actually see that as a bad thing. They are the academic equivalent of buggy whips — well beyond their sell by date. They have no real reason for existence since universities can now publish online very easily.
—-
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 ice.
* Increased cultivation area.
As each of these spread, it will cause an increase in production.
As each of these spreads to a higher and higher percentage of rice producers, the increase in production will slow (for any one of these, when they reach 100%, there is obviously no further increase possible).
This will lead to a decrease in the rate of increase.
Unless the “study” has compensated for these factors it is useless.
I assume that there were actual experiments carried out under controlled conditions to prove the hypothesis that holding daytime temperatures steady but increasing nighttime temperatures by some minuscule amount (< 0.5C) demonstrated that yields were reduced, and that the reduction followed incremental changes in those nighttime temperatures?
(I will not be holding my breath for the experimental results. Nor for so called "reviewers" to demand experimental verification where such is so eminently feasible).
This is so typical of social manias: anything that happens is caused by the thing that one is obsessed with. and if we have to fabricate a bit to make sure everyone understands how important the obsession is, well that is OK.
The commodities bubble greatly increased the value of rice, pulling lower quality fields into production, which should lower the average output per hectare.
Anthony – I’m a farmer in Australia (wheat, barley, chickpeas and lupins) and I know sweat f/a about rice cropping except that it needs a reasonable drink and won’t grow if the seed is still sitting on the back of a truck. However and with hand on heart I can rebut this press release in one word, “Bullshit”. I would therefore like to submit a portion in the rebuttal article defining actually what “Bullshit” is and, how it looks good if an expert scientist, that knows less about growing rice than me, can actually use it as a fly repellent. Of course this is not ordinary bullshit, this is adjusted bullshit, where factors like crop disease, varietal choice, plant and soil nutrient levels, a common old drought (100% probability +/- 25 yrs), weed competition, insect attack, weather events (hail, bush fire, flood, late frosts etc – 100% probability +/- 25 yrs) and generally poor agronomy are removed from the data.
Notwithstanding, the very real reason that the rebuttal article should only include the word “Bullshit” is because of the fact that the rice yields in Asia have dramatically increased according to a more authoritarian and unadjusted source, that has actual equity in the production of rice, namely the ‘International Rice Research Institute”.
There you go Anthony – that’s my article !!!!!!!
I haven’t time to construct a response, and the comments above more than handle the issues raised. I can only provide a link to an appropriate graphic for the assignment given:
http://www.carnivalshooter.com/wp-content/themes/azul/images/shooter/presskit/screen4.png
Reference to yields means different things when relating to terms production and productivity. Production is absolute while productivity is a ratio. The study blurs this distinction.
Temperature fluctuations in tropical countries are within a narrow band. Consequently, even in a “cold year”, it cannot be very significant. Whereas water availability (rainfall) is where we experience wild swings. The farmer plan their cropping seasons according to monsoon expectations. If he thinks there would be good rains he opts for rice or otherwise switches to some other crop, less water dependent. Only those with assured irrigation can afford to stick with rice during a drought year.
Last year, India’s rice production fell a whooping 10%. But what is important to notice is net sown acreage fell by more than 15% – clearly indicating increase in productivity even when the country’s total production fell by 10% due to drought impact.
Nature got it wrong too (http://blogs.nature.com/news/thegreatbeyond/2010/08/temperature_increases_damage_r.html).