Leave It To the Heat to Dull Autumn's Glory (wsj.com)

It's autumn. Somebody tell the trees. From a report: Ordinarily, two signals alert deciduous trees that it's time to relinquish the green hues of summer in favor of autumn's yellows, oranges and reds. First, the days begin to grow shorter. Second, the temperature begins to drop. But this year, unseasonably warm weather across most of the U.S. has tricked trees into delaying the onset of fall's color extravaganza. Temperatures in the eastern half of the country have been as much as 15 degrees above normal since mid-September, and the warmth is expected to persist through the end of October. The unfortunate result for leaf peepers is a lackluster fall. Two kinds of pigments produce the season's liveliest foliage. Carotenoid, responsible for yellows and oranges, is always present in leaves but is usually masked by chlorophyll. The initial trigger for its appearance is shorter days. Anthocyanin, responsible for reds and deep purples, is different. Not all deciduous trees have this pigment, and those that do manufacture it from scratch in the fall. The primary trigger for its appearance is lower temperatures. Without that cooling cue, the colors of maple and other species that generally ignite New England with brilliant reds this time of year are likely to fizzle.

Comments

Not a sign of global warming

[Anonymous Coward]

Remember, global warming is based on the global average temperature. This is regional and is on the timescale of weather rather than climate. During the same time period, temperatures might be below normal in Canada or Eurasia. It would be incorrect to blame this on global warming because this is on a regional scale and it would conflate weather with climate.

Looking at the world around us

[Geoffrey.landis]

Seems to me that explaining the world around us is of interest to nerds.

Not all "news for nerds" has to be "here's the latest update about Ruby on Rails implementation on Ubuntu run on a Raspberry Pi to mine bitcoin."

Re: Darn?

[Captain Splendid]

If you live on low quality flood prone land, MOVE.

And when ~2 Billion people have to do just that, what do you think's going to happen to those of you "smart" enough to live in the hills?

Re:Darn?

[PopeRatzo]

(1) We have had an unseasonably warm fall.
(2) Cooling temperatures trigger the production of red and purple pigments in leaves.
(3) We expect to see less red foliage this year.

Explain to me which of these statements is *political*.

The one that contains the word, "warm". Everyone knows that every mention of warmer than usual weather is an affront to the orange god-king.