The California heat of the past 12 months is like nothing ever seen in records going back to 1895. The 12 months before that were similarly without precedent. And the 12 months before that? A freakishly hot year, too. 

What's happening in California right now is shattering modern temperature measurements—as well as tree-ring records that stretch back more than 1,000 years. It's no longer just a record-hot month or a record-hot year that California faces. It's a stack of broken records leading to the worst drought that's ever beset the Golden State.  

The chart below shows average temperatures for the 12 months through March 31, for each year going back to 1895. The orange line shows the trend rising roughly 0.2 degrees Fahrenheit per decade, just a bit faster than the warming trend seen worldwide.

The last 12 months were a full 4.5 degrees Fahrenheit (2.5 Celsius) above the 20th century average. Doesn't sound like much? When measuring average temperatures, day and night, over extended periods of time, it's extraordinary. On a planetary scale, just 2.2 degrees Fahrenheit is what separates the hottest year ever recorded (2014) from the coldest (1911). 

David Fuller's view

This is not the first time that I have covered California’s water problems, and I maintain that the State has been slow to proceed with desalination.  I know the arguments: procrastination in hope that the problem may be temporary; recycled waste water and imported water are cheaper, desalination plants are ugly and ruin the coastline; the electricity bills for desalination are too high.

The reality is that California is blessed with an enormous coastline.  It should not risk its hugely productive agricultural sector, which the entire country needs, by further delaying the development of large desalination plants.  These do not have to look like monstrosities and can be made more attractive or disguised.  California is also the ideal location for solar power which can be part of the desalination plants.

Get on with the challenge, California, and if you end up producing too much fresh water you can sell some of it to Texas.     

(See also: Desperate from Drought, California Turns to Desalination, and, Could desalination solve California’s water problem?)