The Climate Moe'uhane in Hawaii

The National Climate Assessment has some interesting things to say about Hawaii, like this:

In Hawai'i, average precipitation, average stream discharge, and stream baseflow have been trending downward for nearly a century, especially in recent decades.

I see four NOAA climate regions in the state: Hilo (1950), Honolulu (1905), Kahului (1955), and Lihue (1939).  The start of continuous records is given in parentheses.  Thus, there is only one region (Honolulu) in Hawaii that has records dating back "nearly a century," and precipitation varies widely among the regions.  Precipitation at Hilo averages about 7-fold higher than at Honolulu.

There is also a very poor correlation (r2=0.11) between annual precipitation at Honolulu and Hilo, so if you want to try and extend the precipitation record back in time at Hilo using Honolulu as a proxy, the quality of the results will be poor at best.

But according to the NCA, "average precipitation ... [has] been trending downward for nearly a century, especially in recent decades."  In three of the four Hawaiian regions, we have no data available for "nearly a century."  As for the "especially in recent decades" portion of that sentence, we have a major problem.  There have been no significant trends in annual precipitation for any of the Hawaiian sub-regions since 1970.

The NCA goes on to state that "surface air temperature has increased and is expected to continue to rise over the entire region."  That is interesting.  Of course, warmageddon is just around the corner.  We all know that.  It is like the End of Oil – always just a few years away.  According to the NCA, "in Hawai'i and the Central North Pacific, projected annual surface air temperature increases range from 1.5°F by 2055 (relative to 1971-2000) under a scenario of substantial emissions reduction (B1), to 3.5°F assuming continued increases in emissions (A2)."  Indeed, those sure are large increases, especially for the business as usual option.

On the contrary, there has been absolutely no trend (aka massively non-significant) in annual temperature at Hilo since 1980, 1990, or 2000.  A complete absence of evidence of any warming.  No trends over any of these time periods at Kahului, Lihue, or Honolulu, either.

What about the claims that average stream discharge in Hawaii is trending downward in recent decades?  Of the 29 USGS hydrometric monitoring stations in the state with continuous annual stream flow data going back to at least 1970, only one has a statistically significant declining trend.  There is one stream with an increasing trend, and the other 27 of 29 streams show no trend over the past four-and a half decades.

So we have problems with the NCA's view of climate change in the Aloha State – to go along with every other region of the U.S. examined to date.  But don't question that settled science.