In Ojai, global warming + summer = heat. But how much?

A week ago New York magazine published a blockbuster climate change story. Here’s the annotated/footnoted version. Highly recommended, because the writer — David Wallace-Wells — finds a way to bring home the urgency, using current science. It’s very simple, really. Instead of focusing on what will happen next year, or next decade, or by 2040, he looks at what will happen over the course of this century.

Here’s the cover, to bring the message home:

TheDoomedEarthcatalogue2

To put it simply, even if we as a species succeed in holding warming to 2 degrees Celsius this century, that still means a 4C warming by 2100, which means substantial portions of the planet will become uninhabitable.

From the story:

Since 1980, the planet has experienced a 50-fold increase in the number of places experiencing dangerous or extreme heat. The original paper is by James Hansen, though for this and much of my account of extreme heat events I relied on Joseph Romm’s Climate Change.; a bigger increase is to come. The five warmest summers in Europe since 1500 have all occurred since 2002, This is from the World Bank’s very helpful 2012 report Turn Down the Heat, on life in a world four degrees warmer. and soon, the IPCC warns, simply being outdoors that time of year will be unhealthy for much of the globe.The warning appears on page 15 of the Fifth Assessment’s Synthesis Report. As some readers have pointed out, these effects will come about gradually, beginning with the rare unusually hot day; those unusually hot days will gradually become more frequent in number. As with all of the climate effects in this article, it’s important to remember that heat stress is not a binary matter: It’s not that there are two options, lethal heat waves and normal, comfortable temperatures, but that global warming will gradually bring about more and more heat stress. The same is true, of course, for effects on agriculture, economics, conflict, and other areas. As Richard Alley told me, “We’ve warmed the world one degree. The general impression is that each degree is more costly, more damaging, than the previous one. The first degree — most estimates are that the first degree was almost free. But we can see a dotted line into Syria. The second degree will cost more than the first degree. You might say it costs the square of the warming.” Even if we meet the Paris goals of two degrees warming, cities like Karachi and Kolkata will become close to uninhabitable, annually encountering deadly heat waves like those that crippled them in 2015.“Even if such aspirations are realized, large increases in the frequency of deadly heat should be expected, with more than 350 million more megacity inhabitants afflicted by midcentury,” this paper warns. At four degrees, the deadly European heat wave of 2003, which killed as many as 2,000 people a day, will be a normal summer.Also from Turn Down the Heat. At six, according to an assessment focused only on effects within the U.S. from the National Oceanic and Atmospheric Administration, summer labor of any kind would become impossible in the lower Mississippi Valley, and everybody in the country east of the Rockies would be under more heat stress than anyone, anywhere, in the world today.The report can be found here. As Joseph Romm has put it in his authoritative primer Climate Change: What Everyone Needs to Know,heat stress in New York City would exceed that of present-day Bahrain, one of the planet’s hottest spots, and the temperature in Bahrain “would induce hyperthermia in even sleeping humans.”This is from page 138, though it refers to the same NOAA study mentioned above. The high-end IPCC [Intergovernmental Panel on Climate Change] estimate, remember, is two degrees warmer still.

Several scientists pushed back against the article’s conclusions (and, I suspect, against the graphics and headline, which transmitted a message of doom and extinction). I’ll mention a couple of worthy voices in this debate, but move on to the local issue, which is of greater importance to residents to Ojai.

Ojai is already a warm place in our long Mediterranean summers: what if it gets hotter? Could Ojai be one of those places that will within our children’s become inhabitable?

This graph from NOAA shows that June temps have been soaring as of late. Probably this is due to the drought: without the evaporation and transpiration of water from the ground, temperatures warm more quickly than would otherwise be the case. But still…

CAdivisionsixmaxtempsinJune

 

The question of how much Ojai could warm this century has not really been asked, to my knowedge. Can we stand to consider this possibility? Anyone interested in the answer to that question? What if it’s knowable?

This week NOAA (the National Oceanographic and Atmospheric Administration) held its monthly climate call for media. Climatologist Jake Crouch mentioned in his presentation that “typically when we have really warm years in the lower 48 we see a drought pattern.”

So I (Kit Stolz) asked the natural follow-up: Is there some unusual factor, ocean warming or something not necessarily seen in the usual datasets, that could explain this unusual warming?

Crouch said, in effect, no. “As to the temperature outlook, we saw some natural ridging building across the southwest, bringing hotter temperatures and some human health impacts to the region. We think it’s more of a weather phenomenon than any other factor.”

So there you have it. Until some new research comes in, anyhow.

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