David Lobell is the Benjamin M. Page Professor at Stanford University in the Department of Earth System Science and the Gloria and Richard Kushel Director of the Center on Food Security and the Environment. He is also the William Wrigley Senior Fellow at the Stanford Woods Institute for the Environment, and a senior fellow at the Freeman Spogli Institute for International Studies (FSI) and the Stanford Institute for Economic Policy and Research (SIEPR).
Dr. Lobell is interviewed here by atmospheric scientist Andrew Dessler PhD of Texas A&M.
The “CO2 is Plant Food” crock has been around since at least the early 90s, when the Western Fuels Association produced the film “The Greening of Planet Earth” to promote the idea that carbon pollution was “good for plants”.
There is an argument made that “NASA research says the Earth is actually getting greener”, which needs a little attention.
China’s outsized contribution to the global greening trend comes in large part (42%) from programs to conserve and expand forests. These were developed in an effort to reduce the effects of soil erosion, air pollution and climate change. Another 32% there – and 82% of the greening seen in India – comes from intensive cultivation of food crops.
Land area used to grow crops is comparable in China and India – more than 770,000 square miles – and has not changed much since the early 2000s. Yet these regions have greatly increased both their annual total green leaf area and their food production. This was achieved through multiple cropping practices, where a field is replanted to produce another harvest several times a year. Production of grains, vegetables, fruits and more have increased by about 35-40% since 2000 to feed their large populations.
How the greening trend may change in the future depends on numerous factors, both on a global scale and the local human level. For example, increased food production in India is facilitated by groundwater irrigation. If the groundwater is depleted, this trend may change.
“But, now that we know direct human influence is a key driver of the greening Earth, we need to factor this into our climate models,” Nemani said. “This will help scientists make better predictions about the behavior of different Earth systems, which will help countries make better decisions about how and when to take action.”
The researchers point out that the gain in greenness seen around the world and dominated by India and China does not offset the damage from loss of natural vegetation in tropical regions, such as Brazil and Indonesia. The consequences for sustainability and biodiversity in those ecosystems remain.
The bottom line from Dr Lobell:
Me: So are you worried about the climate impacts on agriculture?
David Lobell: Yes. I think the evidence is very clear that, on net, the changes going on in the atmosphere, including all the climate changes, are a risk to a lot of major production systems and to a lot of food insecure areas. So there’s definitely a reason that we that we continue to work on how to adapt to these changes.
I made my first “Climate Denial Crock of the Week” video on the “CO2 is Plant food” crock way back in 2010, the year Russia banned exports of grain due to the worst drought and heat wave in 1000 year.
Stanford researcher Noah Diffenbaugh appears at about 8:05 talking about his research showing surprising increases in the incidence and severity of heat events – something we have indeed seen playing out.
It’s interesting to see what other predictions have played out in the intervening years.
I’ve posted recently on the impact recent climate extremes have been having on agriculture.
Among all the farmers across the world who are now seeing conditions they have never seen before, safe bet not many of them are saying “If only we had some more CO2..”.
In Greece, people are counting the cost of the devastating floods that hit the centre of the country after Storm Daniel in early September.
Fruit trees, corn and around a fifth of Greece’s cotton crop have been destroyed and over 200,000 animals and poultry killed.
Estimates by academics suggest the short-term effects alone could cost the Greek economy up to 5 billion euros ($5.3bn; £4.3bn).
One of the worst hit areas is the Thessaly plain, in central Greece.
Thessaly is one of the country’s main agricultural regions, and there are fears about the impact on food production.
–
In the nearby village of Lefki, Thanassis Thodos showed us what was left of his walnut orchard. He used to have a thousand trees. Half of them are now destroyed.
“The damage is enormous because the trees have been infected by bacteria… You can see this tree, it is green, but the leaves are starting to turn yellow, which means it may be diseased.”
The limiting factor in plant respiration is water. The first stage in photosynthesis involves the hydrolysis of H2O by photons