Climate change makes food more dangerous

February 23, 2011 By Joel N. Shurkin, Inside Science News Service
Packaged meat in a supermarket.

Global warming has the potential to make what we eat more dangerous and expensive, and the world already is feeling the effects, according to experts.

A quartet of scientists reporting during the annual meeting of the American Association for the Advancement of Science in Washington last weekend said the issues of food safety are poorly understood, but the inference from what is known is distressing.

They fear that global warming would lead to increased levels of contamination of food, from chemicals and pesticides to crop pests and fungal pathogens, as well as faster spreading of diseases such as cholera and shellfish poisoning. These issues could also force changes in diets as some foods become less available or more dangerous and increase in a world where they are already rising and causing civil unrest.

Discussions about the link between climate change and food safety are only now beginning, said Sandra Hoffman of the Department of Agriculture, and the science is not clear.

While poor countries, particularly in the tropics and subtropics and the impoverished everywhere will fare the worst, according to Ewen C. Todd, of Michigan State University in East Lansing, Mich., the threat is not restricted to the developing world.

There are 38.4 million cases of food poisoning in the U.S. every year, mostly from noroviruses, the pathogen best known for affecting cruise ship passengers. Of those victims, 72,000 people are hospitalized and 1,600 die. Salmonella, a , now is the leading cause of food-related death.

Scientists know that for every degree the ambient temperature rises above 6 degrees Celsius -- or 43 degrees F -- temperature in an area, the occurrence of food-borne salmonella poisoning increases by 12 percent.

The dangers can readily be demonstrated, Todd said. In 2005, lettuce grown in Spain and shipped to Finland caused 56 cases of . The cause was traced to farmers using untreated water for irrigation. They had to do so, they told authorities, because a drought, likely produced by climate change, restricted their access to clean water.

Another possible effect of climate change is in the news now. One of the reasons for the unrest in Egypt and Asia has been rising food prices caused by stressed ecosystems on the land and in the ocean, Todd said.

Ray Knighton, also of the USDA, said changing climate affects food production. Drought can cause a loss in plant vigor, making plants more susceptible to disease; floods and heavy rains favor the growth of fungal pathogens on leaves, and many disease-causing organisms can spread in changing wind currents.

"Greenhouse gasses and atmospheric pollutants change plant structure and the ability of the plant to defend itself against pathogens," he said.

Most scientists believe climate change is producing more severe storms and these apparently help spread diseases.

One classic example is Asian soybean rust, spores that cause gold speckles on the light green leaves and eventually kill the plant. The spores spread from Asia to Africa then to South American and finally the United States. The spread in the U.S. was unusually fast and wide. It turns out the spores were riding on the winds of hurricanes from the Gulf of Mexico, Knighton said.

That has huge implications for how food-borne diseases are monitored and the need for a sensitive network for tracking pathogens, he said.

Vibriosis, which comes from seafood, is known to increase with rises in the temperature and salinity of the oceans, said Hoffman. It peaks in the heat of summer. One species of the vibrio bacteria causes cholera. As temperatures rise, the implication is that the spread of vibriosis also will rise.

Increased water temperatures also can lead to increased mercury contamination of fish by 30-50 percent for every increase in degree Celsius, said Cristina Tirado of the University of California at Los Angeles. Desertification, another probable result of climate change, increases pesticide concentration in plants, she said. Flooding leads to soil contamination, and even biofuel production could be affected.

The danger of could mean people change what they eat, Tirado added, avoiding foods grown where climate change has altered the path of germs and potentially increasing the price of food. One and a half billion people already pay 80 percent of their income for food and an increase in food prices would mean "more hunger and less money for health care and education."

The scientists admitted a contradictory effect of climate change: the possibility that some areas, particularly in the north, not now able to grow extensive crops, will warm up and begin to grow more food. Additionally, the cause and effect between and food security is not well-defined.

Part of the problem, Hoffman said, is that data on the incidence of foodborne disease is imprecise and hard to come by.

"There is significant uncertainty about all of this," Hoffman admitted. "We don't know what direction those cumulative effects will be." That uncertainty, she said, will make difficult to design an effective adaptation policy.

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3.2 / 5 (13) Feb 23, 2011
I doubt that the authors could have anticipated that this news item on the dangers of climate change would be published when

a.) The US House of Representatives voted to end funding for the UN's IPCC, and

b.) The Climategate scandal is rapidly unfolding in public:



With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
2.5 / 5 (13) Feb 23, 2011
Is there anything at all, I mean whatsoever, that is bad, that is not caused by either Global-Whatever-They're-Calling-It-This-Week or Bush, Cheney or Palin's mysterious uterus? What's next - halitosis, flat feet, the munchies, all caused by the same bogeymen?

Geez, find a new villain for a change, leftlings.

It's getting boring already, beating you over the head with the same faux Hockey Stick.
3 / 5 (6) Feb 23, 2011
Is there anything at all, I mean whatsoever, that is bad, that is not caused by either Global-Whatever-They're-Calling-It-This-Week ...

And similarly ... Is there anything GOOD that could ever possibly result from Global Warming? Apparently not, as far as the media is concerned.
2.5 / 5 (11) Feb 23, 2011
"There is significant uncertainty about all of this," Hoffman admitted. "So we're only ever going to focus on the worst of all 'possible' worst-case scenarios, because doing so has been successfully and scientifically proven to be the ace bull-moose gold-medal all-time winning methodology for keeping the scientific study funding gravy train a'rollin'."

I paraphrase, of course.

IF global warming were taking place, and I submit to you that that's still deep, deep in the "unproven" category, and would be even without all the falsified data and outright fraud, but if it were taking place there is a long catalog of likely benefits to mankind, including a vastly increased amount of arable land coupled with increased rainfall in areas currently arid. This door (if it were a door and not just a figment) swings both ways.
2.2 / 5 (10) Feb 23, 2011
Dr. Manuel! Good to see your post!

You know, (true story) I once met a woman who had been a paralegal before being convicted of forgery (of some signatures on legal papers, not of money - which would have made this story much more interesting admittedly). Several years after her conviction she was unable to find work - even as a receptionist - in the legal field. Which I though quite appropriate!

In the same spirit, I think the IPCC, Britain’s Climate Research Unit, and any other involved culprit should be not welcome at the table anymore. Ever. I never expected that my opinion of climate scientists (in specific) would one day be lower than that of lawyers (in general).

On a completely unrelated note, I wanted you to know I've enjoyed reading your cosmological research/theories. Not sure if I agree (or for that matter understand) it all, but it certainly is an admirable body of work!
1.8 / 5 (5) Feb 23, 2011
duplicate post deleted (I hope)
2.2 / 5 (10) Feb 23, 2011
The panic in the warmist doom and gloom articles says it all, even the lame stream media doesn't print them up as much anymore, why? because even a stupid leftist newspaper has to sell to survive and the AGW crap has become a another boring page turner. You alarmist are a dieing breed due to your own greedy lies, manipulation and crying wolf to many times, live with it.
3.2 / 5 (9) Feb 24, 2011
Rather than trolling global warming articles, why don't you deniers go do the research yourselves and get published?
3.2 / 5 (9) Feb 24, 2011
Wow the deniers are coming in massive numbers now.

All there arguments are dumb also, i bet someone has an agenda here.

They wont do any research to prove GW to be wrong, cause they know they are wrong themselves. trols...
3 / 5 (8) Feb 24, 2011
Is someone who believes in a theory that has been proven to have been based upon (and sold to the public via) fraudulent data, who then goes on to label those not likewise convinced with insulting names like "deniers" and "trolls" themselves a form of troll?

Sorry guys, I didn't come on here to hunt down and blast global warming articles. I really enjoy, but feel free - in the spirit of open give and take, honest inquiry, and robust skepticism, to point out that with which I vehemently disagree. And why.

As for the sage advice to "go do research yourselves and get published", I'm not aware of that being a prerequisite for participation on this board, but I'll certainly take it under advisement. Please wish me luck - I understand that some of those who now stand accused of data fraud openly admitted to making it très difficile for contrarian voices to be heard or published (and advised colleagues to do the same). So, you know, the deck kind of comes pre-stacked...
3.3 / 5 (7) Feb 24, 2011
Rather than trolling global warming articles, why don't you deniers go do the research yourselves and get published?

Probably because they have jobs that actually contribute to society rather than suckling on grant money to fuel self-indulgent research fantasies.
2.5 / 5 (8) Feb 24, 2011
Nah, Probably because the are paid for by Koch industries, and they are too busy screwing over the unions in Wisconsin.
2 / 5 (5) Feb 25, 2011
Rightlings, sooooo wrong, and loving it!
1 / 5 (4) Feb 25, 2011
Rightlings, abusive, right or wrong and loving it.
2.1 / 5 (7) Feb 25, 2011
Regarding Judith Curry, here is one for you:

"htp://" (add the extra 't')

As one NASA official said; Gavin Schmidt, a climate scientists at NASA, summarised Curry accurately and succinctly:

"In future I will simply assume you are a conduit for untrue statements rather than their originator."

He was being kind at best, IMHO.
not rated yet Feb 27, 2011
Local food production is the way of the future. Imagine the vast number of hours spent playing video games in any given American city, instead went to tending local community gardens requiring no distant transport.
2.3 / 5 (6) Feb 27, 2011
Nah, Probably because the are paid for by Koch industries...

Geez, you leftlings all seem to have developed a pathological case of Koch-envy, all coincidentally about the same time they started getting astro-turfed by your handlers a couple months ago. You do know, of course, that the evil Kochs are also for gay marriage, contributed $20 million to the ACLU to challenge the Patriot Act, are for the legalization of drugs, and lots of other things that the left loves so much. That's what's tricky for you demonizing libertarians (look it up, for those of you in Rio Lindo), because they have views that transcend left-right.
and they are too busy screwing over the unions in Wisconsin.

Correction "PUBLIC SECTOR" unions, who have been busy screwing over WI and every other state that allows them for decades, by taking their dues and buying mainly Democratic candidates that will give them more money and bennies. 40% of the members vote Republican, but 90-98% of donations go to Ds.
2 / 5 (4) Feb 27, 2011
God dang it you people need to grow up, we are pumping toxins in to our air at a rate which should scare even the most conservative scientist, first people dismiss global warming as a product of solar maximum, then you find other reasons, how long before you just freaking admit you have massive carbon monoxide induced brain damage causing your suborn, idiotic behavior?
3 / 5 (2) Mar 01, 2011
I'm sticking to the "trolls" remark because this article is not about the validity of global warming, it's about the effects of global warming on our food supplies.

If you want to debate the article, talk about the fact that most of the material contained in it is speculation, and very little can be directly linked to an increase in global temperatures.

But we don't get that debate. We get "global warming isn't real because Climategate." Changing the subject to something inflamatory, to me, is trolling.
2.6 / 5 (5) Mar 01, 2011
Strange how the little denialist little trolls all decide to descend on the one article.....hmmmm

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