Tracking Ocean’s “Landfalling Droughts” Can Improve Drought Prediction

A study that the Stanford University published on 24 September 2020 revealed a new type of landfalling drought that researchers were able to track from the oceans where it originated before travelling to land causing extensive and drier conditions compared to droughts that solely occurs on land.

We don’t usually think about droughts over the oceans, and it may even seem counterintuitive says the lead author Julio Herrera-Estrada.

However, this type of drought exists. All droughts that occurred in the land between 1981 to 2018, 16% were landfalling droughts or those that originated from the ocean. 

Landfalling droughts are much larger (220 to 425%), more intense (4-30%), and can grow and intensify faster than droughts that start and end only on land, the study says.

The study says that “While the role of sea surface temperatures has been studied in relation to drought development over the continents, fewer studies have analyzed moisture deficits over the oceans. Our results suggest that monitoring and tracking moisture deficits offshore has the potential to yield improvements in drought prediction, warning, and preparation.”

Researchers are studying the physical processes of landfalling droughts that frequently occur in western North America and found that landfalling droughts are linked to specific atmospheric pressure patterns that reduce moisture.

Further investigation may also reveal similar or new explanations for the same droughts that occur in other parts of the world like New Zealand, Chile, Eastern Australia, and Argentina, the study says.

The finding of the study is vital because these landfalling droughts are significantly more extensive and severe compared to their non-landfalling counterparts.

Being able to track them can provide an early warning that would help communities and areas affected to mitigate and prepare for its effects.

To read the entire study, CLICK on the link below:

Source Citation:

Julio E. Herrera‐Estrada, Noah S. Diffenbaugh. Landfalling Droughts: Global Tracking of Moisture Deficits From the Oceans Onto Land. Water Resources Research, 2020; 56 (9) DOI: 10.1029/2019WR026877