Liza Gross, who writes for Inside Climate News, covers California climate, agriculture, drought and water news. Her articles are a good example of how global warming has complex and dangerous consequences that few people are even aware of.
Lisa is especially good at explaining how small changes, like slight increases in temperature, soon branch out into all kinds of unforeseen consequences that in turn blossom into more and more disasters, all of which soon lead to the destruction and ruin to interlinked and crucial ecosystems.
Much of this damage looks like it may be irreversible and all of it is leading to devastated ecosystems and lower agricultural productivity and even worse damage to the fragile world we live in. Lisa makes it very clear how we are caught in vicious cycles and consequences that very few people even realise are happening and which will be extremely hard to correct.
Global warming is far more dangerous and damaging than almost everyone realises.
Below is the beginning of a recent article by Lisa Gross that illustrates all of this. The article from which the below excerpt is taken is titled “In California’s Farm Country, Climate Change Is Likely to Trigger More Pesticide Use, Fouling Waterways.” The article appears in the May 10 issue of Inside Climate news. The theme of the article is that “Warmer temperatures boost pest populations, causing farmers to use more insecticides that, with more frequent and severe storms, turn into toxic runoff.”
Inside Climate News, by the way, is one of the best sources of climate and environmental news out there. I highly recommend it.
Below are the beginning paragraphs of the May 10 article by Lisa Gross.
“Every spring, California farmers brace themselves for signs of wriggling organisms destined to launch multigenerational attacks on their crops.
Many insect species survive the winter as eggs or larvae and then emerge in early spring as the first generation to feed and breed on millions of acres of California vineyards, orchards and row crops. Climate change will complicate farmers’ efforts to control these pests in complex and unpredictable ways.
The most alarming consequence is apt to be ramping up pesticide applications, with broad implications for the safety of California’s waterways—just as the state gears up for a future filled with drought.
Temperature strongly influences insect growth, development and reproduction, while carbon dioxide can affect insect feeding behavior. Higher temperatures will allow some insects to mature faster, helping them fit in extra generations and spend more time flying around fields, reproducing and feeding on crops. They include the moth that can destroy nearly a third of an almond or pistachio crop as larvae. Higher carbon dioxide levels can boost the growth of crops, only to give their primary pests more to eat.
Such climate-driven changes may force farmers, faced with a boom of insects capable of doing more damage throughout the season, to spray more pesticides. And that could trigger a series of events that send more pesticides into sensitive aquatic ecosystems.
California has always cycled through droughts and storms, with both expected to become more frequent and severe under climate change. Heavy rains will saturate soils and aid the flow of sediments and chemicals from fields.
“Eighty percent of the chemical load that gets into our stream network occurs during the 20 percent highest intensity rain events of the year,” said Linda Lee, an agronomy professor at Purdue University. Yet management practices can’t cope with the heavy downpours that account for most of the runoff, she said.
Moreover, when the ground becomes saturated, carbon dioxide can build up in soil and displace the microbial communities that break down pesticides. “Once you get drainage, everybody’s happy again,” said Lee. “But if climate change is causing more intense and more frequent intense rain events, then we could have a problem.”
Lee, though, is less concerned about carbon dioxide buildup in soil than she is about the effects of heavy storms on agricultural runoff. Most worrying are the storms that happen soon after a pesticide application. “That’s going to shove that pesticide into our aquatic system,” Lee said.
California Farmers Are Spraying More Insecticides
A spike in insect populations can lead to a jump in crop diseases, which could also lead to more chemical applications, said Jason Rohr, chairman of the Department of Biological Sciences at the University of Notre Dame.
Many infectious plant diseases are spread by insects, he said, raising concerns that as insect populations expand with the changing climate, so will the diseases they spread among crops.
That means climate change could deliver a twofold blow to agricultural ecosystems: first by increasing populations of harmful insects, triggering more pesticide use, and then by enhancing the movement of pesticides through the watershed, exposing threatened native fish and other aquatic species to higher concentrations of toxic agricultural chemicals.
More reading on the fact that warming has complex consequences
Here are four more articles by Lisa Gross. They all illustrate the fact the even slight increases of temperatures lead to complex and devastating consequences for California agriculture and eventually to all of us humans and to our human societies.
Here are a few more images of our fragile earth.