Saturday, November 09, 2013

Typhoon Haiyan

Typhoon Haiyan is a terrible storm – one of the worst for some time. We should do what we can through the Red Cross to help the victims of this storm. We should also do what we can to support initiatives aimed at anticipating and adapting to such storms in the future.

But Typhoon Haiyan is not a product of global warming or climate change. This is according to those who have dedicated a significant part of their career to studying such storm and their cause. Extremely intense tropical cyclones are rare, but have always been a part of nature — we don’t need to find an excuse for them. Weather officials said Haiyan had sustained winds of 235 kph (147 mph) with gusts of 275 kph (170 mph) when it made landfall. By those measurements, Haiyan is comparable to a strong Category 4 hurricane in the U.S., nearly in the top category (5). In the list of such events in the Phillipines, catalogued since 1896 (see here), it is important but not the most severe in history, as some have claimed. Over past 1,000 years, Philippines have been hit by 10-20 thousand tropical cyclones.

So why do some seek to make a connection to global warming when those who research typhoons and hurricanes have repeatedly made clear that the link cannot be shown. Many such writers acknowledge that it is unscientific to attribute any particular weather event to global warming. But then, in the same breath, they’ll say that this or that typhoon or hurricane is “consistent with” the types of weather ”scientists” predict will become more frequent in a warming world. As Roger Pielke Jnr has observed:

“…climate activists have turned up the rhetorical heat on extreme weather in recent years. The reasons aren’t hard to fathom. The 15-year pause in global warming makes it harder to scare people about warming itself. The two greatest terrors featured in An Inconvenient Truth — rapid ice sheet disintegration leading to catastrophic sea-level rise and ocean circulation shutdown precipitating a new ice age – have no credibility. Nobody takes seriously the prospect of warming-induced malaria epidemics either. If you want to scare people, extreme weather is the only card left in the climate alarm deck.”

Pielke, Jr. acknowledges that considerable research “projects” various weather extremes to become more frequent or intense in the future as a consequence of anthropogenic climate change. However, even if those projections prove correct, “it will be many decades, perhaps longer, before the signal of human-caused climate change can be detected in the statistics of hurricanes (and to the extent that statistical properties are similar, in floods, tornadoes, drought).” Even the IPCC (AR5) accepts that the link between climate change and extreme weather events cannot be shown with any confidence.

So saying that there is such a connection is not a scientific act, but a political one – one aimed at securing the actions required to reduce emissions. It’s a scientific pilgrimage, not science.

No comments: