October 26, 2016

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.


  1. Alright you got me I-732 Cliffy! Still no on ST3! Doesn't make a big enough dent in emissions to off set the cost. The money should be invested on our current roads to make them ready for autonomous in the next few years.

  2. I-732 will increase the price of all goods and most services as everyone must pay for increased fuel and transportation costs. Even locally grown food will increase in price, as farmers are not exempt from the fuel tax. Those who must commute by car will pay way more for fuel at $.25/gallon tax than they will save in sales tax. Manufacturers will get a 4% windfall profit from the reduction in B & O tax. Will we, the people, see any of that in price reductions? It may be revenue neutral, but not for most of us. We, the people will pay the price.

  3. Stop promoting I732!!! It will push heavy industry overseas where there is VERY LITTLE environmental control, making this worse!!! Keep industry here and tariff imports first!

    Chris Neibauer

  4. Perhaps it is just a coincidence or my subjective memory, but it sure seems to me like we're experiencing "what will be normal by the end of the century" more and more these days.

  5. So there's no actual evidence that a wet October isn't just outlying weather in the same way that ice storms in Portland in the early 80s were not also outliers. But the same models that are way off with current and past predictions of warming say that wet Octobers mean warming. Oh and a commercial for I-732. This is not science, it's conjecture and political advertising. Vote no on 732 and you'll be in line with most Americans that rank climate as dead last in the list of urgent priorities that face humans today.

  6. Cliff,
    Thanks for helping to clarify what I-732 is about and for getting the message out. There has been an awful lot said about it in the press that is wrong, ambiguous, or biased.

  7. Some year-to-date comparisons of precipitation over the past 15-16 years. Data from the NWS for Sea-Tac.

    Seems this year is a 'wet sandwich': starting extraordinarily wet and apparently ending with above-ordinarily wet, with a long dry spell in-between. Hold the mustard.

  8. I think we should be clear on what to expect for the tangible benefits of I-732. The EPA's climate model used to evaluate these things says that permanent elimination of ALL of Washington State's GHG emissions would reduce warming by 0.00025 degrees C by 2100, which of course is essentially zero. So I-732 would accomplish a fraction of zero. As the AEI piece here says, it's all cost and no benefit, and that's what's not to like.


  9. In my opinion full or near full reservoirs are a GOOD THING! I would be much more concerned with drought than excessive precip. Cliff, we should be grateful rather than concerned that more CO2 is giving us better water security here in the NW. How is that a reason to vote for an energy tax that will do nothing to impact our climate??? Interesting note, Euro-Asia is having one the coldest Octobers on record with above average snow cover.

  10. It is NOT revenue neutral for my place of work. We are not a "business", we are a non profit adult family home that serves adults with developmental disabilities, and we use energy to power the home, we use gas to drive the clients around to their jobs, to shopping, social activities, etc (they do take some public transportation, but that is limited, and that cost will no doubt rise) We will not see any lower costs due to this initiative, only higher costs. Meanwhile, the state every year raises the license fees and lowers the payments to our adult family home, so raising our energy prices may be the final straw that closes us down and sends our residents back to their parents, who in some cases are not able to take them, and it also means that they will not be able to keep their jobs that they have in our communities, the friendships they have with each other, and their involvement in our community that they have because they are able to live here. All that for .0000001 degree of warming that this may or may not prevent.

    But people who write these initiatives don't think about people like us, and they certainly do not care about people with disabilities.

  11. I'm curious how the record-breaking wet October around Seattle is related to the record-breaking dry October for much of Southeast Alaska. It's not been dry, exactly, just much less wet than normal (October is typically the wettest month of the year for much of the region). Is it simply a matter of where the jet stream is taking low pressure systems this fall?

  12. http://www.thestranger.com/slog/2016/10/20/24628971/we-believe-you-should-vote-no-on-initiative-732

    1. The Stranger's official endorsement is a decisive yes on i732.


  13. We have a lot going against us on global warming. For argument sake I'll assume the intergovernmental panel of scientists are correct in assuming humans are responsible for the vast majority of the problem.
    1) The lag effect- US carbon emissions have declined, yet airborne co2 concentrations are increasing. This implies a delayed effect (policy from 30-50 years? ago is being felt now). So what we do now to mitigate "may" help by that time period forward.
    2) China and India make up most of Global GDP growth going forward and they have far less environmentally responsible policy. A very compelling argument is "why don't they deserve their industrial revolution too?"

    The true "free market" mechanism will come when advances in technology make it more cost effective to refrain from emitting. If weather events of recent years truly have a link to GW and are only expected to get more extreme, we simply don't have the time for politically charged gradual reductions, that may only ever gain traction in the US and EU.

    Appears the only fix will be in figuring out a way to neutralize/reduce existing co2 concentrations and future emissions globally, either by release from our atmosphere into space or chemical manipulation.

    Clearly I'm not a scientist, but maybe someone can shed some light into if anything credible is in the works?

  14. Thanks for your advice, Cliff. You are a valuable resource when I vote.

    My wife and I have already voted. Yes on I-732 and yes on ST-3. In the past I have valued your input on the Seattle school board elections.

    Many thanks for your outstanding blog.


  15. Viewing this, I wonder what the impact will be on the salmon reds in the Elwha and other PNW rivers. Do these eggs get washed away in the deluge? October seems particularly bad timing. I'm certainly not skilled in this area but I would be interested in what other's might have to say.

  16. I don't understand the water vapor flux figure. Will October have 80+ days in 2100?

    SeaTac will have a record total October rainfall this year, but Kent, with just 7.56" as of Oct. 26, will not. But they do appear to be getting more intense rainfalls. Three of the five heaviest one-day rainfalls since 1950 have occurred this century at both locations, with SeaTac getting a record 5.02" on Oct. 20, 2003.

    If you're looking for extremes, however, look to Kent in Dec. 1949, with a record 1-day rainfall of 6", a 3-day of 11", and a 5-day of 15.5".

  17. Wow... all this negative blow back on I 732 support
    Ever think, ever think about why, who's feeding this?

    Sales tax and WA taxes are the most regressive
    in the Nation save maybe one or two other States.
    I'm all for rolling back sales taxes - why do I pay 30% tax and
    others maybe no tax? fixing/lessening climate change? I'm
    all in.

    Do your job! Vote Yes on 732

  18. As a Western Washington farmer I strongly oppose I732. Please vote no.
    I732 will increase carbon emissions and damage our local agricultural community. I732 will only encourage the importation of food, to Washington.

    A positive approach is the answer not I732!!

    For example, I just purchased a thousand dollars worth of Biochar to apply to my fields. (It reduces fertilizer usage and improved soil tilth, plus sequesters carbon!!)

    I paid WA tax on it.!! Why? Farmers should be encouraged not punished!

    We should have tax breaks, to improve our soils, produce more local food, and sequester carbon instead of more taxes. Also why not make more Biodiesel available in this state through tax breaks and incentive?

    732 is negative and will not reduce carbon emissions, only change the location to out of state.

    Take positive approaches instead incentive programs are the right choice, not I732!

  19. While my sleep this week has been disrupted by a pager, I woke up this morning two hours early sweating bullets after having bad dreams for a few hours to find that, indeed, it was way to warm in the room. I get up fairly early in the morning and have managed to find the Roosevelt HS "personal weather station" on weatherunderground, and it has never been below 53.x for the past few weeks (though it has been fluctuating along with the wind speed meter, though it's still possible the outputs are purely random).

    Holding near to 60F for the majority of the night makes it very hard to cool my apartment, without going out and getting fitted airplane propellers to exchange the total volume of air every ten minutes. I stumble over to the "plots comparing recent data to averages" and find that, indeed, SeaTac has been holding above the normal lows for most of the month.

    I'm not saying it's "hot", but it's not cooling at night.

  20. More on how I 732 is nothing but a feel good guilt relief tax for the more affluent.

    If you live in a desirable urban neighborhood, and can ride your bike to work. Ask yourself a question. Do your servants live in the same neighborhood?

    Likely no, they can not afford the luxury, of high rents in upscale neighborhood's. SO.. they are forced to commute to the service jobs. Of course these same people can not afford a Prius or a Leaf, and likely drive old cars.

    I732 sticks it to this group unfairly!

    Do you see where anger and resentment and class division is a serious problem. I732 fans those flames further.

    Adding low income housing to affluent neighborhood's will reduce emissions more than a gas tax on the lower class.

  21. It is a proven fact that plants, including trees and all our food crops, are capable of growing much faster at higher levels of CO2 than present in the atmosphere today. Even at the today’s concentration of 400 ppm plants are relatively starved for nutrition. The optimum level of CO2 for plant growth is about 5 times higher, 2000 ppm, yet the alarmists warn it is already too high.

  22. Oct 2003 also had the single rainiest day in Seattle history. we had 5 inches one day that month. I will never forget it because I moved that day. Wonderful day to move!

  23. So warm this afternoon! 66 at the Atmospheric Sciences building, and sunny, and I left my shorts at home.

  24. Cliff,

    Yes I'll vote for this thing, it's a drop in the bucket compared to China and India, not to mention the rest of the USA, but I'll vote for it.

    Heard your talk this morning. wetter Octobers AND more spring clouds? I hope these predictions aren't both right. I assumed that climate change would make our climate rather like that of central Willamette Valley (say, like Eugene). Care to comment?


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