A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).



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Save the world and raze some forests

Look out, another knot of tortured researchers just went past. All this time we’ve been pouring money into planting trees and stealing land from farmers because we were sure that trees would cool the world. (Just like solar panels do, yeah?) But life is so complicated — for years now some researchers have been quietly wondering if more trees were actually going to warm the planet instead, but they didn’t want to say much. It turns out that while trees absorb the sacred CO2 (that’s cooling!) they also emit methane (that’s warming!), and terpenes (cooling) and isoprene (warming and cooling!) If that’s not complicated enough, then there is the albedo effect. Trees are dark, they absorb more sunlight than bare ground and snow. So depending on where they are planted, that makes for “warming”. Then some VOCs or volatile organic compounds also seed clouds.

So what’s the net effect? Who knows, it’s not like there are whole industries dependent on it…

Now they ask?

How much can forests fight climate change? Trees are supposed to slow global warming, but growing evidence suggests they might not always be climate saviours. Gabrielle Popkin, Nature

As usual, the debate is based on [...]

Record hottest year means record bumper wheat crop, opposite of crop models

Last year there were warnings from crop modelers in Nature that heat kills wheat and yields were going to fall in the “near future”, if temperatures rose. In fact global warming was “already slowing wheat gains”. What followed was a record El Nino, and 2015 was the hottest ever year, with 2016 vying to beat it. But instead of wheat doom, this month the USDA forecasts a record yield of wheat with bumper crops globally. Wheat output has grown in Australia, the US, Russia, Ukraine, everywhere pretty much, except the EU where it has been too rainy. Where are the mea culpas?    h/t to the GWPF

Jan 2015, published in Nature.  “Global Wheat Yield May Drop as Temperatures Rise”

“… researchers are now letting farmers know that the world’s wheat yields are excepted decline in the near future, with the world standing to lose six percent of its wheat crop for every degree Celsius that the annual global temperature increases.

“The simulations with the multi-crop models showed that warming is already slowing yield gains, despite observed yield increases in the past, at a majority of wheat-growing locations across the globe,” researcher Senthold Asseng, at the University [...]

CO2 emissions in last 50 years made us $3.5 Trillion wealthier

Millions of people are alive today because the net emissions of carbon dioxide have increased. These extra emissions have provided essential fertilization for crops around the world. Craig Idso has released a new report calculating that the extra value that the rise in CO2 has produced from 1961 – 2011 is equivalent to $3.5 trillion dollars cumulatively. Currently the extra CO2 is worth $160 billion dollars annually. Big-biccies. Projecting forwards, increasing CO2 levels could be worth an extra $9.8 trillion on crop production between now and 2050. Virtually every economic analysis to date does not include the agricultural gains. There are also benefits in health, as warmer winters reduce mortality by more than hotter summers increase deaths. The real economic question then, is “Can we afford to slow CO2 emissions at all?”

While there are negative externalities projected by some climate modelers, their models are unvalidated, proven wrong, and based on unsupported assumptions about clouds and humidity. Compare that to the agricultural gains, which are not just demonstrated in laboratory greenhouses, but confirmed in the field, and with global satellite estimates of increased biomass.

Obviously, the only sensible thing to do at this point is continue our emissions of [...]