Climate tipping point defined for US crop yields

Climate tipping point defined for US crop yields

www.newscientist.com

While news reports and disaster movies remind us about tipping points for Arctic melt and sea level rise, some things closer to home get less attention. Take food supply: new modelling studies show that there are climate tipping points here too, beyond which crop yields will collapse.

"The single best predictor of a year's yield is the amount of time temperatures exceed about 29 °C and the extent to which they do so," they say...

(visit the link for the full news article)

..."Below this, warmer temperatures are beneficial for yields, but the damaging effects above 29 °C are staggeringly large."

Interesting. Terrifying. Well regardless of the anthropogenic link it looks like we could be in for a very rough ride. Maybe it is time we all committed to ensuring we are NOT contributing to this planetary issue, you know just to be safe.

Overall, the results suggest that yields of maize, cotton and soybean drop by roughly 0.6 per cent for each "degree-day" spent above 29 °C.

That's likely to rise as the world warms. Using a model of future climate change the researchers found that the number of degree-days above 29 °C in a growing season could rise to 413 by the end of the century if we do not cut greenhouse gas emissions. This would cause maize yields to fall by 82 per cent.

Ouch. 82% feeds a LOT of people.

Even if we reduce emissions by 50 per cent by 2050 relative to 1991 levels – a target that governments are struggling to agree on – yields could still fall by between 30 and 46 per cent.

Interesting. More fear mongering by the 'experts' or a serious call for action based on the cataclysmic consequences of continued inaction?

I choose the latter but judge for yourself.

The US is the world's largest producer and exporter of crops, accounting for around 40 per cent of global maize and soybean production.

"If US yields go down a lot, it could drive up prices of staple food commodities all around the world", say the researchers. "Almost surely the poor would suffer far more that the US would."

Once again, we are all in this together. Perhaps it was time we started acting like it?

www.newscientist.com
(visit the link for the full news article)

The Govt' actually pays people to not farm their land and to not produce as much food as they could. If we are running out of food just cut Govt' subsidies and let the farmers farm to their heart's content. Problem solved.

On an off topic note; I will be growing all my own vegetables, and taking better car of the fruit trees I already have next spring.

Originally posted by KnoxMSP
The Govt' actually pays people to not farm their land and to not produce as much food as they could. If we are running out of food just cut Govt' subsidies and let the farmers farm to their heart's content. Problem solved.

The 82% decrease in productivity based on climate would still take effect. Unless you are saying we are producing 82% or greater BELOW our potential threshold, which I know is not the case, we still have a problem here.

On an off topic note; I will be growing all my own vegetables, and taking better car of the fruit trees I already have next spring.

My hat off to you mate. EVERYONE should be growing food to some extent. I applaud your self-sufficiency, independence, and pioneering spirit.

Providing ones own life necessities is after all a key element in democracy.

Originally posted by Animal


The 82% decrease in productivity based on climate would still take effect. Unless you are saying we are producing 82% or greater BELOW our potential threshold, which I know is not the case, we still have a problem here.

I don't have figures, but I know my granfather received subsidies to not grow cabbage in one of his plots, and received subsidies to re-zone part of his farm. This was a while ago so I don't know how prevelant it is today, but I know it still happens. Seriously if you took every farm in America and let it grow to 100% capacity, even if the crops are effected by climate change, I believe we could sustain ourselves. Forget other countries, if we get to that point there should be no more exporting of American crops.

I live in Arkansas, where summer temps routinely run in the mid 90's to low hundreds. We've had a cool summer this year. No 100 degree days. But my point is, we raise cotton here. Lots of cotton. Some soybeans, some corn. The yield depends on a lot of varibles. But the breed of crop makes a difference. If the cotton hybred is for high temps, yeilds will be good, all things being equal. The same is true for other crops.
There are a lot of varibles involved with farming that affect yield, which is why, after being raised on a farm, I decided on a different line of work. Love the work, but don't like the gamble.