cold snaps

Geoengineering refers to a wide range of mechanical or chemical methods aimed at deliberately changing the global climate system. It includes a number of unproven concepts, one of which is intentionally polluting the upper atmosphere with thousands of tons of artificial particles such as chemical sprays or mineral dust. This is referred to as solar radiation management or SRM. The idea is to dim sunlight, thereby slowing the rise of global temperatures by deflecting solar energy away from the Earth’s surface before it can be trapped as heat by greenhouse gases in the atmosphere.

The United Nations Environmental Program held workshops in May and September to address the issue of such strategies. This official position of the UN is that strategies such as SRM are not a climate solution given that they do not actually address the underlying causes of climate change. Recent research has shown that SRM efforts could potentially shift rainfall patterns, intensify heat waves or cold snaps, lead to overall drying, and have other unpredictable consequences.

Many participants expressed concern that the discussion focused too much on engineering aspects and not on the potential risks of such efforts. The prevailing opinion among scientists is that SRM deployment is too dangerous and ungovernable and therefore should not be pursued.

Current geopolitical trends make the possibility of geoengineering efforts by authoritarian states disturbingly likely. While there are international guidelines on geoengineering activities, the potential threat of unilateral efforts by rogue nations is growing.

**********

Web Links

UN Sessions on Solar Geoengineering Trigger Unease

Photo, posted May 12, 2016, courtesy of Susanne Nilsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate change is leading to warmer winter weather throughout the southern U.S., providing opportunities for many tropical plants and animals to move north. A new study by scientists at UC Berkeley looked at the changing distribution of tropical species driven by the warming climate.

Some species are appreciated in their new locations, such as sea turtles and the Florida manatee, which are gradually moving northward along the Atlantic Coast. Others, like the invasive Burmese python are not so welcome. That goes double for many insects, such as the mosquitoes that carry diseases like the West Nile virus, Zika, dengue, and yellow fever, as well as beetles that destroy native trees.

The transition zone, northward of which experiences freezes every winter, has always been a barrier to species native to more temperate places. For most organisms in such places, if they freeze, they die. Cold snaps like the recent one in Texas usually don’t happen for decades and are now likely to be less and less frequent. In the meantime, tropical species can get more and more of a foothold and maybe even develop populations that can tolerate more cold extremes in the future.

The warming climate is leading many plant species to expand their ranges, in some cases pushing out native species. The general story is that the species that do really well are the more generalist species whose host plants or food sources are quite varied or widely distributed and can tolerate a wide range of conditions. By definition, they tend to be the pest species.

We need to prepare for widespread shifts in the distribution of biodiversity as climate, including winter climate, changes.

**********

Web Links

Tropical species are moving northward as winters warm

Photo, posted May 7, 2010, courtesy of Jim Reid / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The U.N. meets about geoengineering

Web Links

Tropical Species Moving North | Earth Wise

Climate change is leading to warmer winter weather throughout the southern U.S., providing opportunities for many tropical plants and animals to move north. A new study by scientists at UC Berkeley looked at the changing distribution of tropical species driven by the warming climate.

Web Links