A Winning Wager

The seasonal Gulf of Mexico hypoxic zone remains one of the largest in the world, and several scientists have developed models to help forecast the size of the zone each year. Measurements of the areal extent of the zone have occurred since 1985, and those data typically become available between late July and early August.

Trying to anticipate these measurements provides a “battle of the models” opportunity, as modelers can create their predictions and test their estimates against the official numbers. So this past June, Gene Turner, a professor of Oceanography and Coastal Studies at Louisiana State University and one of the original researchers who started studying the Gulf hypoxic zone, challenged SEFS Professor Sergey Rabotyagov to a friendly scientific wager to test their alternative models.

Sergey Rabotyagov
Professor Rabotyagov shows off the winning prize for his forecast of the Gulf of Mexico hypoxic zone.

Using 2011 and 2012 numbers, Rabotyagov’s model had been more accurate than Turner’s and the other existing model for predicting the hypoxic zone, which was created by Professor Donald Scavia of the University of Michigan. When the hypoxic measurements became available for 2013, though, all three researchers were surprised to find their models over-predicted the size of the hypoxic zone. Professor Scavia’s estimates were actually closest this year, but Rabotyagov’s model did outperform Professor Turner’s model—and since the wager was only between the two of them, Rabotyagov claimed the prize: A frilly Detroit Red Wings beanie.

Still, two out of three for Rabotyagov is pretty impressive, and he also stresses other positive takeaways from these models and data. “Although the comparison of observed and predicted hypoxia clearly suggests that our ability to predict any given year’s hypoxic zone with a high level of accuracy is limited,” he says, “all of the existing models emphasize the role that upland areas have in creating and also mitigating this important environmental issue.”

Turner and Rabotyagov are working together as a part of a National Science Foundation-funded study to figure out how best to reduce the hypoxic zone, and they will likely tweak and test their models again next year!

Photo of Professor Rabotyagov © SEFS; graph below © Professor Rabotyagov.

Forecast comparisons
Comparison of the three models, with Professor Rabotyagov’s in green. His estimates were the closest to actual numbers in 2011 and 2012, and in 2013 his model performed second of the three (but bested Professor Turner’s to win the wager)!

Thesis Defense: Joshua Simpson!

Originally from Illinois, Joshua Simpson served in the Illinois Army National Guard from 1999 to 2005, including a 12-month tour in Iraq. He was awarded the Purple Heart and an Army Commendation Medal. He then studied GIS and environmental science at Northern Illinois University and graduated in 2007. He moved to Seattle immediately after and, before enrolling at UW to study applied economics and GIS, he built hiking trails, mapped hiking trails and restored environments in the Puget Sound area.

For the past couple years, Simpson has been completing his graduate study at SEFS, and the public is invited to see him present his thesis tomorrow, May 30, at 2:30 p.m. in Anderson 22: “An Econometric Analysis of Sewer Backup Claims in Seattle.”

Joshua SimpsonAbout Simpson’s Research:
Seattle is known for its high occurrence of rainfall events, and most of them are low-intensity events. When it rains heavily, sewer backups occur and, by all accounts, that’s bad news. Damage claims are filed and, in some cases, the city will cover the amount of damage. Sewer backups caused $8 million of damage from August 2004 to March 2011. Most of the damage claims were due to three major storms that occurred within that timeline.

For his thesis, Simpson examined factors that explain the damage caused by those three storms using a rare events logistic regression model. Sewer backups are rare events in Seattle, as the highest claim-producing storm in the city produced 147 claims, while there are more than 180,000 parcels in Seattle. Simpson used the claims from the three storms and a random stratified sample of parcels throughout Seattle to explain the causes of the backups.

Rainfall and soil saturation variables explain most of the damage that occurred, but other factors such as demographic and sewer system variables explain the cause of backups. Simpson used a spatial econometric model to measure the causes of various levels of sewer backup damage. Rainfall, soil saturation, demographic and sewer system variables, as well as tree density, explain the various levels of damage that occurred within the stated time line.

The results of both models were combined together to produce an expected sewer backup damage amount for the sample parcels. This data, along with the separate results of both models, were used to create three maps that represent probabilities of backups (given the results of a particular storm), potential damage and Expected Sewer Backup Damage.

These maps and data can be used to prioritize preventative maintenance before a storm season. There are many other risks that face utility customers in Seattle, but focusing on this risk allows for the application of two econometric models. Such an approach has not been utilized to analyze the occurrence of sewer backups to date. With the results of Salathe et al. (2010) and Zhu (2012) that suggest that higher frequency and higher intensity storms will affect the Puget Sound area, the accumulation of data and the use of the best information can mitigate future damage caused by these storms.

Simpson’s committee chair is Professor Sergey Rabotyagov, and the other members are John Perez-Garcia, Robert Halvorsen and Terry Martin. So come out and support him tomorrow at 2:30 p.m. as he completes his latest chapter in life!

Map graphic © Joshua Simpson.

Thesis Defense: John Simeone!

Simeone Thesis Defense
An 18-wheeler carrying roundwood in Dalnerechensk, Russia.

SEFS graduate student John Simeone, who is working on a joint degree at the Jackson School of International Studies, will be defending his thesis for the latter program this coming Friday, May 3, at 10:30 a.m. in Anderson 22.

While the Russian forest sector languished for much of the first 15 years following the break-up of the Soviet Union, beginning in 2007 the Russian government instituted a set of policies designed to develop and modernize the Russian forest sector. This thesis is a policy analysis of Russia’s 2007 and 2008 forest sector initiatives—principally export taxes on roundwood and investment subsidies for value-added processing.

If you can’t make this Friday’s defense, then keep an eye out for Simeone’s SEFS defense later in August. His faculty advisor is Professor Sergey Rabotyagov, and he is also working closely with Professor Ivan Eastin and CINTRAFOR on Russia’s role in the timber trade. Should be great stuff!

Photo © John Simeone.

SEFS Seminar Series: Week 4 Preview

Hypoxic ZoneA major federal effort quantifying the water quality impacts of cropland conservation practice investments was recently completed for the entire Mississippi-Atchafalaya River Basin (MARB). Additional scenarios of watershed-level targeted conservation practice investments were modeled, and the costs of their implementation were estimated.

Utilizing these unique data, Professor Sergey Rabotyagov will explore several questions about the Northern Gulf of Mexico hypoxic zone, including whether additional conservation investments in the Upper Mississippi River Basin—the basin responsible for the majority of riverine nutrient delivery to the Gulf of Mexico—could cost-effectively reduce the areal extent of the hypoxic zone.

Join Professor Rabotyagov this Wednesday, January 30, for a deeper discussion in Week 4 of the SEFS Seminar Series, “Cost-effective Subwatershed Targeting of Agricultural Conservation Practices to address Gulf of Mexico Hypoxia.”

The seminars, held in Anderson 223 on Wednesdays from 4 to 5 p.m., are open to all faculty, staff and students. Check out the rest of the seminar schedule for the Winter Quarter, and join us each week for a reception in the Forest Room from 5 to 6:30 p.m.

Map of hypoxic zone © Sergey Rabotyagov.

SEFS Seminar Series: Speakers & Topics Announced

Seminar SeriesStarting on January 9, 2013, Director Tom DeLuca will kick off the SEFS Seminar Series (SEFS 550F) for the Winter Quarter with an introduction and the first topic, “Nitrogen dynamics in boreal ecosystems.” Check out the rest of the schedule below, and mark your calendars today!

The seminars, held in Anderson 223 on Wednesdays from 4 to 5 p.m., are open to all faculty, staff and students. Each week, a reception will follow in the Forest Room from 5 to 6:30 p.m. (Graduate students can receive course credit for attending 9 of 10 seminars by registering for SEFS 550F, SLN 20703. Please email sefsadv@uw.edu if you have any trouble registering.)

Seminar Schedule

Introduction to SEFS Graduate Seminar Series: Nitrogen dynamics in boreal ecosystems
Tom DeLuca

The really hidden half of the hidden half: The role of deep soil in forest ecocystem processes
Robert Harrison

Suffer the Buffers: Population Growth and Resource Degradation in Pre-Modern China
Stevan Harrell

Cost-effective subwatershed targeting of agricultural conservation practices to address Gulf of Mexico hypoxia
Sergey Rabotyagov

Environmental stewardship, social equity and corporate profitability: Siblings or strangers?
Dorothy Paun

How can we improve the production of fuels and chemicals from lignocellulosic biomass?
Renata Bura

Reintroducing the water cycle in urban areas
Sally Brown

2/27/2013 (Doubleheader)
3 p.m.: Managing for resilience: Sustaining mountaintop ecosystems in the presence of white pine blister rust
Anna Schoettle

4 p.m.:  Chaos in federal forest policy in PNW: The situation and a proposal
Jerry Franklin

No seminar scheduled.

Modeling greenup constraints in spatial forest planning
Sándor Toth