monsoon

Should We Block The Sun? | Earth Wise

May 10, 2021 By EarthWise Leave a Comment

There is growing concern that greenhouse gas emissions are not falling quickly enough to avoid dangerous levels of global warming. As a result, there is the impetus to examine other options. Among these are geoengineering, which is one of the most contentious issues in climate policy. Geoengineering embodies many risks that make even seriously considering it seem risky in itself.

Despite this, the National Academies of Science, Engineering, and Medicine has issued a report saying that governments urgently need to know whether solar geoengineering could work and what its side effects might be.

Solar geoengineering is also called solar radiation modification, which entails reflecting more of the sun’s energy back into space. This would likely be accomplished by injecting aerosols into the atmosphere, much like what happens after large volcanic eruptions.

Schemes for solar geoengineering raise numerous issues. Although solar geoengineering might cool the earth’s surface to a global temperature target, the cooling may not be evenly distributed, affecting many ecosystem functions and biodiversity. It would likely upset regional weather patterns in potentially devastating ways, for example by changing the behavior of the monsoon in South Asia. It might dangerously relax public commitments to reduce greenhouse emissions.

Despite these concerns, or perhaps because of them, the committee that produced the report believes that technology to reflect sunlight deserves substantial funding and should be researched as rapidly and effectively as possible. Once any geoengineering projects get into the hands of policymakers, they may gather momentum that bypasses the advice of scientists. So, it important to make progress on the science while geoengineering is still only theoretical.

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Should We Block the Sun? Scientists Say the Time Has Come to Study It.

To intervene or not to intervene? That is the future climate question

Photo, posted August 3, 2018, courtesy of Tomasz Baranowski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Widespread Drought | Earth Wise

September 7, 2020 By EarthWise Leave a Comment

As the U.S. enters the last part of the summer, fully one-third of the country is experiencing at least a moderate level of drought. Much of the West is reaching severe drought conditions and New England has been unusually dry and hot. In total, over 50 million Americans are living in drought-affected areas.

According to the U.S. Drought Monitor program, more than 93% of Utah, Colorado, Nevada, and New Mexico are experiencing drought to some degree. More than 60% of both Utah and Colorado are in severe drought. More than three-quarters of Oregon, Arizona, and Wyoming are also in drought. And most of these areas had no sign of drought this time last year.

Severe drought conditions result in stunted and browning crops, limited pasture yields, dust storms, reduced well water levels, and an increase in the number and severity of wildfires.

Warm air temperatures and minimal snowfall in spring set the stage for this summer’s drought conditions. A ridge of high pressure over the northeastern Pacific Ocean pushed the jet stream farther north than usual. And, once again, there has been a failure of the southwestern monsoon in Arizona and New Mexico and the Four Corners region. Monsoon rains provide half of the year’s precipitation in many of those areas.

Instead, there has been extreme heat in the region. Phoenix has already smashed the record for the most days over 110^oF in a calendar year (42 as of August 18), with five months to go. Las Vegas hasn’t seen measurable rainfall since April, and Cedar City, Utah has recorded a record low of 0.05 inches of rain this summer.

Conditions are not expected to get better for a couple of months.

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A Third of the U.S. Faces Drought

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Did People Create The Sahara Desert?

April 25, 2017 By EarthWise

One of the arguments some people make when discussing human causes of climate change is that people can’t cause such massive changes. However, there is a long historical record of human-driven ecological and climatic change in Europe, North America and New Zealand, among other places.