The Real Climate Trends in the City of Angels

In an interview with Dave Ross, the KIRO Radio Morning news anchor in Seattle, University of Washington Atmospheric Sciences Professor Cliff Mass was quoted with the following gem:

"If you're in Southern Canada, climate change is going to be a good thing. If you're in Siberia, it's going to be a good thing. If you're in Los Angeles and the Southwest, it's going to be a bad thing," says Mass. "I think in total, it's going to be a bad thing. Anything that changes from what we're used to is going to probably be a bad thing. But there will be winners and there will be losers."

Anything that changes from what we're used to is going to probably be a bad thing?  Absolutely anything?  There is no chance that any form of climate change anywhere at any time can be a good thing?

Of course, perhaps Mass doesn't realize that this claim entirely contradicts his first two sentences, whereby he states that climate change in southern Canada and Siberia is apparently "going to be a good thing."  And since "climate change" is by definition a change "from what we're used to," it looks like we have a fundamentally incoherent suite of claims.  Climate change can be good, except when it is always bad?  An oxymoron if there ever was one.

Climate change in Los Angeles is "going to be a bad thing"? A good time to see what is actually going on with the climate in the City of Angels.

Since records began in 1878, there has been no significant trend in annual precipitation, nor in precipitation for any one of the individual months.

Over the past 30 years, the average annual temperature has a significant declining trend – aka, cooling  – as do the months of February, April, and June.  Sure, average temperatures in LA increased steadily from the 1880s up to the late 1970s, but then they started to decline sharply.  What is the anthropogenic greenhouse gas emission mechanism for that 135-year-long suite of trends?  Average temperatures in LA are now back down to the neighborhood last seen in the 1960s and 1970s.

Average maximum temperatures exhibit the same types of patterns, with significant declines on an annual basis and in April and June.  The negative correlations during July and August are also evidence that summers in LA are getting cooler in recent decades, not warmer.  Significant declining trends in February and June – and on an annual basis – for the extreme maximum temperatures, too.  In others, the climate in Los Angeles is becoming more moderate and less prone to heat waves.

More evidence of the moderation of LA's climate during the last 30 years comes from the negative correlations in both number of days above 90°F and above 95°F each year.  Same goes with the near-perfect non-correlations for number of days with heavy precipitation events (both for more than one inch, or two inches, of rain) since 1984.  No trend in number of dry days without any precipitation, either.  A moderate climate everywhere we look.

There is a significant decline in the number of cooling degree days (a measure of demand for air conditioning), and a near significant increase in the number of heating degree days (a measure of demand for having to turn your furnace on to keep the house warm).  That sounds like the exact opposite of what the warmists are predicting for LA, and it is consistent with a cooling climate.

The significant decline in growing degree days over the past 30 years in Los Angeles also means residents shouldn't be concerned about too much heat-damaging agricultural crops in the area, but instead, the recent trends suggest they should be worried about not having enough heat units over the summer to ripen the food in their backyard gardens.

Is this climate moderation and cooling what climate scientists mean when they say climate change will be a bad thing for the City of Angels?  Somehow I suspect not.

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