vigorous

Tumbleweeds have long been seen as symbols of America’s old west. Tumbleweeds are a structural part of the above-ground anatomy of a number of species of plants known as diaspores. Diaspores are essentially seed dispersal units. In a few seed plants, they comprise most or all of the plant. Once they are mature and dry, they detach from the roots and roll around due to the force of the wind.

There is a new species of gigantic tumbleweed – the Salsola ryanii – that is expanding its territory in the American west. It is the result of a relatively unusual genetic process known as polyploidy, which produces offspring with multiple sets of chromosomes. Researchers believe that that the new hybrid species of tumbleweed is healthier than earlier versions. As a result, one geneticist described Salsola ryanii as a nasty species replacing other nasty species of tumbleweed in the US.

These tumbleweeds can grow up to 6 feet tall. Tumbleweeds in general are invasive plants that cause traffic accidents, damage agricultural operations, and cause millions of dollars in property damage. Last year, the town of Victorville in the California desert was buried in them, piling up to the second story of some houses.

Salsola ryanii has a relatively small range, but it is expanding rapidly. The new study determined that it is more vigorous than its predecessors, which are invasive in 48 states. The plant is an annual but tends to grow on the later side of winter. It is one of the only things that is still green in late summer. With summer rains increasing as the climate changes, these monster tumbleweeds are poised to wreak havoc. The experts are warning that there should be efforts to suppress them before they take over.

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Monster tumbleweed: Invasive new species is here to stay

Photo, posted February 27, 2018, courtesy of Tracie Hall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Human beings are utterly dependent upon energy both for our well-being and for societal development. Our energy use is highly dependent upon climate since so much energy is expended either keeping us warm in winter or cool in summer. As the climate changes, it is important to understand how energy demand is likely to be affected.

A new study published in Nature Communications by researchers in Austria, Italy and the United States explored this topic. The study is a global analysis using temperature projections from 21 climate models, and population and economy projections for five socioeconomic scenarios. The purpose was to determine how energy demand would shift relative to today’s climate under modest and high-warming scenarios by the year 2050.

The findings indicate that, compared to scenarios in which energy demand is driven only by population and income growth, climate change will increase the global demand for energy by 11-27% by the year 2050 under a modest warming scenario. With vigorous climate warming, energy demand would increase by 25-58%. (Large areas of the tropics, as well as southern Europe, China, and the US are likely to experience the highest increases).

These findings are important because if energy use rises and leads to additional emissions of heat-trapping greenhouse gases, it will be increasingly difficult to mitigate future climate warming. Quantifying this risk provides even more incentive for reducing greenhouse gas emissions before these effects upon demand are realized and it becomes even more difficult to prevent further impacts.

Policymakers need to be aware that even moderate levels of climate change will lead to increases in energy demand that will make it increasingly difficult to minimize the harmful effects on their societies.

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More energy needed to cope with climate change

Photo, posted December 15, 2008, courtesy of Matt Hintsa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Monster Tumbleweeds

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Climate Change And Energy Demand

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