The Climate in Emergency

A weekly blog on science, news, and ideas related to climate change

Western Pacific Typhoons

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Japan can’t seem to catch a break this year.

Aside from the eruption of Mount Ontake (which was quite a disaster, but tangential to this blog), the country has had a serious problem with weather, especially flooding. Three typhoons have made landfall on the islands so far (Neoguri, Halong, and Phanfone), plus, Tropical Storm Man-yi raked the length of Japan in September, dropping almost twenty inches of rain within two days. At least one non-tropical rainstorm in August caused flooding and deadly mudslides as well. An Internet search for “unprecedented flooding Japan 2014” yields multiple results not all of them from the same storm. 

Japan is large enough that these storms have not all hit the same places, but still, it must be very difficult to be Japanese this year.

Another storm is on the way now, the startlingly monstrous Vongfong. There is some hope that it will weaken before hitting Japan itself, but it is a super typhoon and is one of the most powerful storms on record–ever. It is being compared to last year’s Typhoon Haiyan, the very existence of which convinced many that something has gone really, really wrong with Earth’s atmosphere. Well, now here’s another one.

To be clear, a typhoon is the same thing as a hurricane; different ocean basics use different names for the same type of storm. The collective term for any storm with this kind of structure is ” tropical cyclone.” A tropical cyclone that has sustained maximum wind speeds of 75 MPH or more is a hurricane, a typhoon, or a cyclone, depending on where in the world it is. Tropical depressions and tropical storms are weaker versions of the same thing. A super typhoon is the equivalent of a class 4 or 5 hurricane.

I have found little to no discussion of Japan’s troubles in general, or Super Typhoon Vongfong specifically, in terms of climate change so far. Perhaps the problem is that I can’t read Japanese and so am probably missing the vast bulk of coverage on these storms. I expect that if Vongfong causes a major disaster we may hear more about it here in the English-speaking world.

In the meantime, I am curious–when such discussions do get going, will they have a basis in fact?

Each storm basin produces slightly different storm behavior, with different storm seasons and different numbers of storms being typical per season. The Northwest Pacific basin is the most active in the world; it runs all year, though there is typically a lull over the winter, and its storms are often more powerful than those in the Atlantic. So a season that looks vicious to a writer based in the United States might be normal for Japan. So, is this an unusually powerful typhoon season?

Based on 1981-2010 data, the NW Pacific can produce anywhere from 14 to 39 storms of tropical storm strength or more, with an average of 26. Of these, anywhere from 5 to 26 are typhoons, the average being 16.5. Since 1960, the number of super typhoons per year varies from 1 to 11.

Getting a reliable list of the actual storms in this season is difficult, probably because English sources focus on the two basins that can threaten the United States and the NW Pacific cannot. By comparing several different blogs and news sites–not all of which agree with each other–I conclude that Vongfong is the basin’s ninth typhoon and its sixth super typhoon. These numbers are right in the middle of the typical range for the last several decades, but since the year still has three more months to run, this does look to be a busier than average year–but not an extraordinary one.

I am not a climatologist, so I could easily be contradicted here, but it looks like the only extraordinary thing this year–so far–is Vongfong. That might be enough. And of course, climate change does not cease to play a role in the weather when the weather is average or even calm; global warming is not an event but an element within all events. And even if the frequency of this year’s storms is not unusual, storm surges and total rainfall are higher than they would be without global warming. Recently I made a rough tally of the people who die of global warming? Get ready to add a few more when Vongfong rolls in.

Part of the reason I wanted to write about the Pacific storm season this week is simply that I know most of my readership is American, and American media (somewhat understandably) focuses on American news. I wanted to post a reminder that extreme weather still happens even when it isn’t happening here (though, of course, parts of the US are suffering from extreme weather as well).

But the other reason is that I’ve been watching the Pacific, expecting an extreme season, just as I’d been expecting a mild Atlantic season. This was supposed to be an El Niño year. As I said this spring:

El Niño refers to an unusual weakening of the trade winds, which causes warming of certain parts of the Pacific ocean. The name means “the Child,” referring to the Christ Child, because of the bad fishing the warm water causes off of Peru around Christmas during El Niño years. The pattern radically changes the weather across much of the globe. For example, El Niños partially suppress Atlantic hurricane activity but increase hurricane formation in the Pacific. A stronger trade winds and a cooling of the Pacific is called La Niña (“the Girl,” because it is the opposite of “the Boy”) and likewise alters worldwide weather. The Pacific moves between these two extremes every three to seven years for reasons no one really knows. The cycle is called ENSO, for El Niño Southern Oscillation.

When I wrote that, signs were good (or bad, depending on your perspective) that an El Niño was going to develop. It has not not happened yet, though it is still possible. Apparently, the Pacific waters have warmed, but other aspects of the El Niño pattern have not developed. I don’t know whether this year’s quiet Atlantic hurricane season is related to this almost-Niño or not. The busier than average Pacific season probably is, since the Pacific has been warmer than usual, and tropical cyclones feed on warm water.

An interesting question is whether the Atlantic is also warmer than usual? It might well be, if the relative lack of hurricanes is due to increased wind-shear (as it would be in an El Niño year). That is, warm water can cause increased storm activity, but decreased storm activity does not, all by itself, mean the water is cool.

The thing is that nobody knows what drives the ENSO, and so nobody knows its real relationship to climate change. It’s a reasonable guess that we could be in for more frequent or more severe El Niños, since both involve warming water, but we can’t be sure. Something else besides warm water might be necessary, and without that something else, more frequent El Niños might not happen.

I’m wondering if perhaps this is what the future looks like? Pools of warm water forming in the Pacific (and possibly elsewhere), causing some of the effects associated with El Niño, but not all of them? If so, Asia had better watch out.

If anyone has further insight on this, please drop me a line.

 

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Author: Caroline Ailanthus

I am a creative science writer. That is, most of my writing is creative rather than technical, but my topic is usually science. I enjoy explaining things and exploring ideas. I have one published novel and another on the way. I have a master's degree in Conservation Biology and I work full-time as a writer.

One thought on “Western Pacific Typhoons

  1. Pingback: It’s *%@$ing Cold | The Climate Emergency

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