Climate

In August and September 2015, a massive dust storm swept across the Middle East, engulfing seven nations in sand thick enough to ground flights, trigger respiratory distress for many, and obscure the region from satellites. At the time, the unprecedented size of the storm was blamed on the ongoing conflict in Syria, with unusual amounts of dust being raised from abandoned agricultural lands and increased military traffic. But a new study cites a combination of climatic factors and weather as the more likely culprits.

Explosive volcanic eruptions can spew sulfur gas into the stratosphere — the layer of the atmosphere above where most clouds and weather occur — where it forms sulfate aerosols that reflect sunlight back into space and cool the planet. Now, researchers investigating how volcanic plumes could be affected by projected anthropogenic warming have found that, as temperatures rise, it becomes more difficult for volcanic plumes to reach the stratosphere.

Fly over the tropical or subtropical oceans and you’ll see a white blanket of clouds covering the blue-green water. These low clouds, typically forming less than 2 to 3 kilometers above the ocean surface and covering up to 40 percent of Earth’s surface, play a critical role in the planet’s energy balance. Now, new research using satellite data and climate models to investigate how these clouds respond to climate change shows that they play a large role in regulating climate sensitivity.

Water seeps through soil and bedrock before dripping from the roof of a cave and carries with it elements of the outside world and its climate history. That is why speleothems, cave structures formed via precipitation, can be studied as climate proxies. New research suggests that the chemistry of the cave dripwater can also contain the signature of wildfires that burned outside the cave, on the ground above the cave’s roof, yielding a more complex picture of the past.