Sunday, May 29, 2016

Trump vs. Data

Trump: “They don’t understand it. There is no drought, they turn the water out into the ocean.”

Data:


7 comments:

Victor Venema said...

I was afraid you would have data how Mossack Fonseca pays me a monthly fee from the Chinese government to destroy American manufacturing.

Richard Mallett said...

So the trend is -0.04 inches per year = -1.02 mm. per year.

David in Cal said...

The chart shows that there was a severe drought, but that the current year precipitation is at a normal level. Here in Silicon Valley, our usage level is still set at 37% below our base period usage.

Whether or not the downward slope of the fitted precipitation line is predictive is debatable. In any event, that slope is miniscule. OTOH, there is a clear, large upward slope is the population of the state. It's up by 2500% since the year 1900 and up by 5% since 2000. California's shortage of water is caused by population growth, not long-term change in precipitation.

http://www.infoplease.com/ipa/A0004986.html

David Appell said...

US Drought Monitor
http://droughtmonitor.unl.edu/

David in Cal said...

Warming might cause a water problem, separate from precipitation trend. Since there's little or no rain on the coast in the summer, the water supply depends on the snow pack in the Sierras. A high amount of rainfall in the mountains is considerably less helpful than a high amount of snow.

Cheers

David Appell said...

Warming always contributes to a drought, because (1) it reduces snowpack, and (2) it increases evaporation, exponentially.

David in Cal said...

I agree with (1). But, (2) is less clear. Increased evaporation over the entire oceans has the potential to lead to increased rainfall over land.