Title is somewhat incorrect: more than 60% of the U.S. is facing drought, making it overall the worst in decades. The data do not show that the drought in each area is the worst in decades.
The drought map used here is partly subjective opinion.
> Meteorologists and climatologists from the NDMC, NOAA and USDA take turns as the lead author of the map, usually two weeks a time. The author’s job is to do something that a computer can’t. When the data is pointing in different directions, they make sense out of it.
> How do we know when we're in a drought?
> No single piece of evidence tells the full story, and neither do strictly physical indicators. That’s why the USDM isn’t a statistical model
Doesn't seem like all climate scientists are fans of it either. From a 2022 critique of a news story also based on this map:
> The essential message is that weather and climate data do not support the claims of extreme or severe drought in eastern Washington this year.
> There is no expectation of water problems over or near the Columbia Basin. The Drought Monitor graphics, which are created subjectively, are sufficiently problematic and deficient that they should not be considered or applied to any serious decision making.
> [Authors] bring together the physical climate, weather and hydrology data and reconcile that with local expert feedback, impact reports and conditions observations. The author is also responsible for weighing different indicators based on what’s most appropriate for a particular place and time of year. In the West, for example, winter snowpack has a stronger bearing on water supplies than in the East
It also sounds like that old adage of - All models are wrong but some are useful. Alas, we probably only know how useful they where afterwards.
Title is somewhat incorrect: more than 60% of the U.S. is facing drought, making it overall the worst in decades. The data do not show that the drought in each area is the worst in decades.
The drought map used here is partly subjective opinion.
https://droughtmonitor.unl.edu/About/WhatistheUSDM.aspx
> Who draws the map?
> Meteorologists and climatologists from the NDMC, NOAA and USDA take turns as the lead author of the map, usually two weeks a time. The author’s job is to do something that a computer can’t. When the data is pointing in different directions, they make sense out of it.
> How do we know when we're in a drought?
> No single piece of evidence tells the full story, and neither do strictly physical indicators. That’s why the USDM isn’t a statistical model
Doesn't seem like all climate scientists are fans of it either. From a 2022 critique of a news story also based on this map:
https://cliffmass.blogspot.com/2022/04/is-large-portion-of-w...
> The essential message is that weather and climate data do not support the claims of extreme or severe drought in eastern Washington this year.
> There is no expectation of water problems over or near the Columbia Basin. The Drought Monitor graphics, which are created subjectively, are sufficiently problematic and deficient that they should not be considered or applied to any serious decision making.
And a lot of hard work, sounds like: https://droughtmonitor.unl.edu/About/AbouttheData/DroughtCla...
> [Authors] bring together the physical climate, weather and hydrology data and reconcile that with local expert feedback, impact reports and conditions observations. The author is also responsible for weighing different indicators based on what’s most appropriate for a particular place and time of year. In the West, for example, winter snowpack has a stronger bearing on water supplies than in the East
It also sounds like that old adage of - All models are wrong but some are useful. Alas, we probably only know how useful they where afterwards.