The Wettest October on Record, Global Warming, and I-732

After a very wet day on Wednesday, it is now clear that Seattle will exceed the all-time record for precipitation in October: 8.96 inches that fell in October 2003

And as I will explain below, it provides a dramatic reminder why voters in Washington State should support Initiative I-732, which will reduce carbon emissions in our state and could lead to a nationwide movement for effective restriction of greenhouse gas production.

The numbers

As of 10 PM on Wednesday, the rain gauge at Seattle Tacoma Airport had 8.84 inches, .12 inches less than the record.  With rain falling overnight and several more storms coming this week, there will not be any trouble breaking the October record.  We will be breaking a major record.

What makes this month so remarkable is that most of the precipitation fell in a very soggy two-week period that began around October 13th (see plot of observed precipitation--blue line-- below)

Global Warming and October Precipitation

We can not conclusively point to global warming as the "cause" of this month's substantial rainfall.   It could be the result of the random, chaotic nature of the atmosphere.  But I can tell you that climate models driven with increased greenhouse gases show a dramatically increased amount of early fall precipitation, particularly during October.   In fact, I have been actively researching this issue with UW scientist Michael Warner.

Seattle's reservoir levels have zoomed up with all the rain (red line), 

with current values similar to what are usually observed in December.

Below is a figure from a paper we just submitted to a peer-reviewed journal.  It is a bit complicated so let me explain.  Our goal was to see how the frequency of extreme precipitation days will increase under global warming in our region during the 21st century.  The blue symbols represent the numbers of days in each month that a measure of extreme precipitation potential (called the  water vapor flux) exceeds the 99% value for the current period using a collection of models.. The median of the various models is shown by horizontal line in the middle of the rectangle.  The red figures show that same thing at the end of this century, assuming we keep up our current fossil fuel burning ways.

A very large increase, particularly in the fall.  October's increase is the largest of all.

 A number of papers in the literature show consistent results:  under global warming we expect the most extreme precipitation events to increase (because warm air holds more water vapor than cold air) and that the greatest increases will be in early fall.

So although we can not definitively point a finger at global warming as the causal factor this month, by the second half of the century we can expect global warming to make such wet Octobers much more frequent.  We are getting a taste of our future if greenhouse gases continue to rise.

I-732 is Critically Needed to Deal with the  Global Warming Threat

There is no time to wait on dealing with the increasing levels of CO2 in the atmosphere.  We need a powerful tool to reduce emissions in our State, one that will be so attractive that it can spread to rest of the country.

Initiative 732 is such a powerful tool, one supported by a wide range of groups, including over 50 climate scientists at the UW, the Audubon Society, the Stranger, The Weekly,  The Olympian many Democratic organizations, Republican and Democratic state legislators, major political figures of our region (e.g., ex-Congressman Jim McDermott), the Seattle Green Party, and many, many more.

Initiative 732, uses the most effective approach for reducing emissions, the free market system, by taxing carbon emissions.  Economists of both political persuasiona agree that taxing carbon is the most effective approach for reducing carbon emissions, and this method has been tried with great success in British Columbia, and several nations around the world.

Initiative 732 is revenue neutral, returning all the proceeds back to citizens.   This has some wonderful consequences.  First, the money is used to reduce the sales tax and provide a low-income household rebate.  The result is that Initiative 732 works to make our take system less regressive, which is good since WA State has the most regressive taxation in the nation.  Second, by not increasing the size of government, 732 is attractive to folks of all political opinions.  It can be bipartisan.

Effective reduction of greenhouse gas emission can't be a Democrat thing or a Republican thing--only by devising an approach that both sides of the aisle can support can we develop a policy that can pass in WA State and have a good chance of spreading to the rest of the nation.

I-732 has a real chance.  Current polls (Elway) show that it is about 8 points ahead, but there are still lots of undecided voters.  Some folks have been spreading false information about whether it is revenue neutral (it is, as close as humanly possible).  Others want to harvest the revenue and use them for their pet projects and help their particular groups.  Not only is government ineffective in picking winning approaches (Pronto bicycle anyone?), but a revenue positive approach would make the State's tax laws MORE regressive, hurting low-incoming and minority communities.

Effective in reducing greenhouse gas emissions, bipartisan, makes the tax system fairer, highly progressive, and free market.  What is not to like?

The record breaking precipitation this month is a warning.  Will we be wise enough to take action before greenhouse warming profoundly changes our climate?  If you are a WA State voter, it is in your hands.