Tuesday, March 7, 2017

No water problems this summer

If anyone was worried about water resources for next summer over the Pacific Northwest, stop worrying.  We are in excellent shape.

And with lots of water and a good snowpack, there are less fears for an early or severe wildfire season.

Let's look at the situation in detail.

During the past month, the region has been quite wet, with much of the area receiving 150% and more of normal precipitation.
The snowpack is normal over Washington and well above normal in Oregon (see below).  Plenty of snow to melt in the summer to supply water to fill streams and reservoirs.

The critical Yakima River reservoirs are in good shape and are currently slightly below normal.  Snowpack melting and precipitation the next few weeks should be able to fill them.
Seattle's reservoir storage is above normal and the snowpack above Seattle's reservoirs is near normal.  Seattle is in excellent shape.

What about the huge water storage for Everett's system at Spada Lake?  It is at 95% of normal (it was higher but they brought it down for flood protection). Red line is current level and blue is normal.

So everything is in very good shape and there is a lot of precipitation in the forecast.   And March precipitation is worth more than November precipitation.   Dam and reservoir operators are less worried about flooding so they can store more of the water.  And if it is raining, then the ground is not drying out and water demand remains low.

For the next 360hr (15 days), the National Weather Service GFS model has unimaginable amounts of precipitation over our region (see below). Like 10-20 inches of precipitation over the mountains.

The NOAA Climate Prediction Center 3-month forecast is for wetter than normal conditions.

All this precipitation is bad for parents watching their kids play soccer or little league.  But good for  skiing, water resources, agriculture, power generation and those worried about wildfires.  Water is life and in the NW critical for the economy.  And we will be well supplied until this fall.


Jackie Long said...

Yes, but what about the webbing growing between my toes?

iamlucky13 said...

It's puzzling to me see in the first graphic those isolated patches that seem to be hundreds of square miles of below 25% of normal precipitation completely surrounded areas of 100-200% of normal precipitation. Is that some kind of data artifact, or does for some reason rain simply not fall at normal rates persistently for specific areas for the entirety of a single season?

FYI, Spada Lake never has trouble this time of year. During the 2015 drought, while local leaders were deliberately misleading residents by talking about running out of water by February, the regular fall rains they were pretending didn't exist had the reservoir full again by late November. See the green line on the graph you shared.

Where Spada Lake can potentially get into trouble is the low snowpack, hot summer situations like 2015. Spring runoff ended early, summer inflows were unusually low, and water use was unusually high. Yet, they never even had to reduce the amount of water they were spilling for fish flows, which accounted for over twice as much water as the peak Everett usage. Keep in mind, without the dam holding that water at Spada Lake, in years like 2015, fish trying to spawn on the Sultan River would have had far less water. Spilling 300 cfs is an incredible ecological luxury enabled by the fact that we store so much.

This year, Spada Lake was full by the end of October. If we insist on maintaining high fish flows even during extreme drought years, we may some time down the road exceed Spada Lake's storage capacity, but we'll have to work at it. If that happens, the solutions would be either to enlarge Culmback dam to allow more storage in Spada Lake, or drilling wells to utilize a tiny fraction of the massive groundwater rights that Everett owns, which likewise in our area is easily recharged by precipitation.

TheWildLine said...

Not entirely convinced everything will be fine since we could have record breaking heat this summer from runaway global warming.

Plus the dams and dikes will be at risk if it all melts at once.
Remember what happened to Vanport?

Andrew said...

It rains a lot here is an understatement.

Cliff Mass said...

Wildline.... there is no runaway global warming and no reason to expect record-breaking heat....cliff

CG said...

Hi Cliff! Random question but I can't find another place to ask you. I live in Kenmore and have often posited the theory that Kenmore is situated in some kind of banana belt where the clouds break in such a way around us that it seems more frequently sunny than in other parts of the Seattle area. They look as if they split apart in the hills to the west of us and then recongregate over the lake. Is it possible to have a very mini microclimate like that? Do you think I may be accurate? And is there a way to test the theory? Thanks!

Jim Price said...

"record breaking heat this summer from runaway global warming"

If you accept Cliff's analysis, climate change is happening at a relatively slow, steady rate. The most dramatic impacts are in the Arctic, and it is impossible to know to what extent global warming is exacerbating a given heat wave, storm, or fire season. There may well be tipping points in the future where factors like melting permafrost, reduced ocean ice and changing ocean currents combine to measurably accelerate warming, but I haven't seen any evidence that we will hit one of those this summer, and even such a spike would only be detectable after years, not months.

Remember that the Dust Bowl happened before human-caused climate change was a factor. This shows that natural variability can produce extreme summers without the help of climate change. Human-caused warming is certainly having an effect, but it is so small relative to the impact of natural variability that it is impossible to determine the extent of the impact. In 30-50 years (absent extreme emissions reductions or a few large volcanic eruptions), the impact of anthropomorphic climate change will be undeniable.

If we insist that every hot summer or big hurricane is the result of global warming, it gives climate change deniers air cover to claim that every record cold snap disproves global warming.

iamlucky13 said...

@ Jim Price:
"If you accept Cliff's analysis, climate change is happening at a relatively slow, steady rate. "

Not just Cliff's, but also the IPCC, which almost exclusively deals with the long term trends, not the weather. Chapter 14 of the Working Group 1 Assessment Report does address regional weather trends, but it is extremely general. For example, here's what the summary says about hurricanes and other cyclones (my emphasis added on language that reflects their uncertainty):

"Based on process understanding and agreement in 21st century projections, it is likely that the global frequency of occurrence of tropical cyclones will either decrease or remain essentially unchanged, concurrent with a likely increase in both global mean tropical cyclone maximum wind speed and precipitation rates. The future influence of climate change on tropical cyclones is likely to vary by region, but the specific characteristics of the changes are not yet well quantified and there is low confidence in region-specific projections of frequency and intensity."

For some other phenomena like monsoon season behavior, they indicate high levels of confidence, but are still very general.

Some other groups look more closely at weather. If I remember right, UW has done a fair amount of work attempting to model how the Pacific NW weather will likely change, for example.

bob5568p said...

Hi Cliff, was driving yesterday and noting the rain/snow mix. I was musing on why two drops of precip could be so near each other, but one snow while the other remains rain.

Clearly some variable is different. Is it mass? Or is it micro-differences in the surrounding air the bits move through?


Charlie Barbour said...

In the Colorado Rockies, big snowpack often led to MORE wildfires because plants grew bigger faster. It's an arid climate. Is that the difference?

Random Menace said...

Jim Price - Your comment got me curious about the causes of the droughts of the 1930s. This paper Amplification of the North American “Dust Bowl” drought through human-induced land degradation hypothesizes it was a combination of both natural and human factors that led to the length and intensity of the drought.

Dalton said...

Regarding the wildfire risk assessment: I actually agree with you this year, Cliff. In past years (particularly after the winter of 2014-2015) you claimed that despite a record low snowpack we had plenty of precipitation (in the form of rain) and so wildfire would not be a problem. Boy howdy, were you wrong about that!

I think you need to pay more attention to ecology and wildfire dynamics of the region and stop blaming strawmen building luxury homes in forested wilderness. The biggest wildfire disasters in the past few years (Pateros, Sleepy Hollow in Wenatchee, and Chelan) were not in forested wilderness, they were in long established communities bordering a sparsely forested landscape consisting largely of scattered trees, sagebrush and critically grass that were close to major bodies of water.

Probably the biggest contributor to these fast moving and unpredictable fires from an ecological perspective is the nonnative invasive Bromus tectorum (cheatgrass). Cheatgrass is a major contributor to high-intensity large-scale wildfires (http://onlinelibrary.wiley.com/doi/10.1111/gcb.12046/abstract). Here's the thing about cheatgrass: it's called cheatgrass because it cheats compared to native grass's by germinating in the fall and its roots continue to grow throughout the winter, and by spring, are capable of out-competing native species for water and nutrients because most native vegetation is just getting started. Cheatgrass completes its life cycle quickly and can become dry by mid-June.

The difference this winter is that we've had a really good low elevation snowpack throughout most of the winter. There's been snow on the ground in Wenatchee since mid-December and it's still there this morning. Hopefully this will have stalled the cheatgrass and give the natives more of a fighting chance.

Thanks for listening and for the positive forecast.

Rebecca Timson said...

For those who want to know more about permafrost and the potential impacts of melting, there is some good research-based information at the National Snow and Ice Data Center. It is neither alarmist nor dismissive.

South Sound Guy said...

I keep hearing this is the coldest winter in Seattle since 1985 and one of the wettest. Why then is the snowpack in the mountains only about average? How were the conditions different which created the monster Cascade and Olympics snowpack during the winter of 1998-99?

TheWildLine said...

Thanks for the response, graphs like these make me think maybe we have reached the runaway stage:


Plus tracking


sunsnow12 said...

"Why then is the snowpack in the mountains only about average?"

I agree with this question Cliff and since you are one of the only bloggers on the subject that appears to value honesty, I would like your opinion on it.

The only independent numbers I know of on snowpack – outside of the USDA - come from WSDOT at the 5 passes they monitor. At the end of February, % of 5-year average: Snoqualmie Pass 140%; White Pass 149%; Blewett Pass 132%; Sherman Pass 139%; Stevens Pass 115%.

Granted these are not SWE (snow water equivalent), but anyone who has been up there knows it has been raining (and then freezing) along with the snow at pass level this winter. There is a lot of water content in the Cascade snowpack this year and if anything I would expect SWE to be higher than these %’s.

There is, once again, something fishy about the numbers we are getting on this. It bothers me when observational data (ski areas (check out Alpental), highway numbers, precip numbers from multiple locations, etc.), conflict with “official” data. Especially when it comes to anything regarding water, since you know from our “wet drought” experience, the entire fall/winter 2015 “ridiculous” (your term) drought, and California’s “permanent drought”, that we are often fed complete bs on this subject.

Put it this way: credibility with this came into question a long time ago. I think it is valid for people to question these snowpack numbers.

iamlucky13 said...

@ South Sound Guy - we've had both a lot of cold weather and quite a bit of rain, but they've tended not to occur together - long stretches of cooler than normal weather separated by shorter, warmer periods with lots of rain, even at higher elevations.

When cooler, wet weather systems have head our way, they've been tending to dip southward a lot this winter, pushing that weather toward northern California. You can see in Cliff's post that while a lot of Washington is around 100% of average, Oregon is mostly in the 125-150% range. California's Sierras are at 185% of average.

@ TheWildLine - there's nothing in that first link that contradicts the slow steady rise. It just shows the jump in CO2 over the last 150 years compared to the prior 400,000 years. That correlates accordingly with the forecast warming for the next 100 years.

The second link is misleading. Methane is already accounted for in the climate models. Atmospheric methane levels have been tracked for decades. A study locating the sources of methane changes how methane's contribution to warming is addressed, but we already knew how much of it was there.

Alan Jones said...

The dust bowl was caused by humans. Converting huge areas to fields got rid of the flora holding the soil in place. Scientific research for changes in farming practices that reduced soil loss is what facilitated recovery.