Friday Headlines, August 30, 2019
THE LATEST IN THE GEOSCIENCES
This week in geology
- Volcanic eruption in Italy
This week in the environment
- Can burning forests cause climate change?
Italy’s volcanic island of Stromboli erupted on August 29 in dramatic fashion.
The cause of all the volcanism in Italy is a sizeable subduction zone where the crust forming the floor of the Adriatic and Ionian seas (the African Plate) is being shoved under Italy and the rest of Europe (the European Plate).
Subduction zones cause numerous earthquakes as one plate slides under the other, as well as volcanoes, caused by the melting of the subducting plate.
Recently, the news has been flooded with reports of massive forest fires, particularly in Brazil, but also in Greenland and Siberia.
The burning of forests can contribute to global climate change in several ways. For one, the massive forests take up atmospheric carbon dioxide, a known greenhouse gas identified as one culprit in the increase in average global temperatures.
Burning of forests also emits carbon monoxide, which is also an important greenhouse gas responsible for increasing global temperatures.
There has been some arguments made that past episodes of rapid global temperature increase may also be related to massive forest fires.
The Paleocene-Eocene Thermal Maximum is a spike in temperatures that occurred about 55 million years ago and marks the boundary between the Paleocene and Eocene epochs.
Fung et al. (2018) provide evidence of widespread and intense wildfires at this boundary using petrological evidence. They find evidence of extraterrestrial impact, in the form of glassy spherules at the Paleocene-Eocene boundary, followed by abundant charcoal.
Whether this impact and subsequent fires caused the warming, is not clear, but it is certainly coincident with the rapid warming at the Paleocene-Eocene boundary.