CGRER Looks Forward: Geographer Eric Tate


Julia Poska | February 8, 2019

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Eric Tate, 2019. Photo by Julia Poska. 

Natural disasters are enormously costly. The U.S. incurred an estimated $306 billion in physical damage from extreme weather events like hurricanes and floods in 2017 alone.

CGRER member Eric Tate, a professor in the University of Iowa geography department,  quantifies disaster impacts in a bigger way.

“Looking at these impacts just by dollars affected may not really get at the true impact of how people are affected, how their livelihoods are affected,” he said.

Tate studies the social effects of disasters, with an emphasis on floods. Looking beyond physical damage, he determines how population characteristics like age, disability, education and poverty create social vulnerability to harm.


Listen to Tate explain social vulnerability in his own words. 

Disaster impacts are typically distributed unevenly; certain groups suffer disproportionately due to social, political, economic and institutional inequalities. These processes may debilitate some households while neighbors go unaffected during the same storm.

Using mainly government disaster relief data, Tate has measured and mapped the social reality of disasters like 2012’s Hurricane Sandy. He’s currently examining 2015 flooding in South Carolina. His research aims to inform planning and policy by lending insight into how various population characteristics contribute to vulnerability.

“What is needed in this field is a bunch of studies looking at different disasters at different scales of analysis, looking at different variables, looking at different outcomes,” he said. “When you put them all together, now you start to get some generalizable understanding.”

Officials can use such analyses to help vulnerable populations before, during and after disasters with adjusted mitigation and primary response plans. The social dimension of sustainability is often underemphasized, but is crucial for implementing effective change.

“If we want to have sustainable futures but the gains aren’t equitably shared, then is that sustainable?” Tate asked.


Tate on the need for research into the spillover effects of disasters. 

He sees several ways policymakers on all levels can more deeply embed equity into decision making. They can model vulnerability among their constituents themselves or look to academic research that does so. They can seek to be inclusive and involve a diverse cross section of the population early on in the decision making process.

Tate pointed to the National Environmental Policy Act as well, which requires the government to complete environmental impact assessments prior to undergoing all federally funded executive projects. He thinks a similar statute could mandate assessments of the far-reaching social consequences of such projects.

He also advised considering climate change in proactive disaster planning, as atmospheric carbon seems to amplify climatological weather events. In Iowa, flooding has already become pronouncedly more intense and will continue to get worse in coming decades.

“Regardless of your belief in climate change or not, we’re seeing changes in hydrological extremes,” Tate said.


Tate on how to help protect yourself and your community from flooding. 

Intensified flooding will increase pressure on the already vulnerability and likely push some previously unaffected households beyond their coping capacities.

Tate calls for updated statistical analysis to better inform everyone from city planners to homeowners about risk and vulnerability in different areas. The 100-year floodplain of today may become the 50-year floodplain in 15 years, but flood maps are based on historical frequencies and do not reflect projections for the future.

“Trying to understand future risk based on past occurrences is likely to lead you to faulty conclusions,” he said. “We should be thinking maybe a little less probabilistically and a little more possibilistically.”

 


***This post is part of “CGRER Looks Forward,” a new blog series running every other Friday. We aim to introduce readers to some of our members working across a wide breadth of disciplines, to share what the planet’s future looks like from their perspective and the implications of environmental research in their fields. ***

 

Polar Vortex breaks Iowa cold records


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Temperatures dipped well below minus 20 degrees Fahrenheit in Iowa on Wednesday (flickr).

Julia Poska | January 31, 2019

Early Wednesday morning, while many across Iowa were still asleep, records were broken by the so-called “Polar Vortex” over the Midwest. Before 4 a.m. Des Moines saw a minus 20 degree temperature, making it the coldest Jan. 30 the city has seen in recent history. Waterloo got an even colder minus 24 degrees, breaking the same record in that city. Farther north, temperatures reached minus 29 degrees, as reported by the Des Moines Register.

Windchill made the cold temperatures feel even more brutal. In Cedar Rapids, windchill Wednesday morning reached minus 55 degrees, a tie with the 1985 record for the coldest windchill ever recorded there. According to the Registerwinds were steadily between 15 and 25 mph, but at times blew into the mid-30s.

Climate change and extreme cold

Some studies suggest that such extreme “Polar Vortex” events in the Midwest could become more common with climate change, though more research needs to be done to make a definitive call on the matter.

It appears that warmer arctic temperatures cause the jet stream, a westerly moving band of air circling the northern part of the globe, to dip farther south, bringing the North Pole’s extreme cold into the United States. Read this article from National Geographic for a more in-depth look at the science.

On The Radio- The impacts of climate change on the Midwest


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A midwest sunset (Sue Varga/flickr)

Kasey Dresser| January 14, 2019

This weeks segment looks at the affects of climate change on the Midwest covered in the Fourth National Climate Assessment. 

Transcript: 

Increased heat and rain will strike Midwest agriculture from multiple directions. 

This is the Iowa Environmental Focus. 

The Fourth National Climate Assessment, released in November, details the impacts of climate change for the Midwest. Productivity in the agriculture sector is a top concern.

The Midwest has long sustained an ideal climate for growing crops, but projections forecast rising temperatures and more intense rainfall in the region, far from optimal for the healthy growth of corn and soy.  

Warmer winters will also encourage survival of pests season to season, and rising temperature and humidity in spring may increase disease outbreaks in crops. 

More intense rainfall will also increase soil runoff, already a major issue in the region. When soil washes off of fields and into waterways, there are fewer nutrients for plants in the field and more in the water, which can fuel harmful algae blooms. 

Scientists project a 5 to 25 percent drop in corn productivity throughout the Midwest by mid-century. Soy yields may fall about 25 percent in the southern Midwest, but could increase in northern states. 

For more information, visit iowa-environmental-focus-dot-org.

From the UI Center for Global and Regional Environmental Research, I’m Sara E. Mason.

Climate Assessment predicts water stress on multiple levels for U.S.


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This graphic from the Fourth National Climate Assessment shows groundwater depletion in U.S. aquifers a decade ago. Today, these underground water supplies are even more depleted. 

Julia Poska| November 30, 2018

We already know climate change is having major impacts on rainfall. The 2018 Iowa Climate Statement said the strongest rainfall events of the year may double in intensity by 2025.  Climate change will alter the hydrologic cycle in other ways as well, majorly changing society’s relationship with water.

The Fourth National Climate Assessment, controversially released Black Friday, details the forecasted changes to water supplies in the U.S.. It compiles the findings of over 300 experts and has been reviewed by 13 federal agencies, in an effort to inform top decision-makers and common citizens.

More intense rainfall will be met with more intense drought and reduced snowpack, which is bad news for communities that rely on glacial melt for their water supply. These changes are exacerbating water availability issues caused primarily by overuse of groundwater aquifers in much of the U.S..

As higher temperatures create even higher demand for water for drinking and irrigation, this problem will only get worse and worse, which will have major implications for both the food supply and the industrial sector.

The altered hydrologic cycle will impact the quality of our limited quantity of water as well. Rising water temperatures will impact the health of ecosystems, and changes  runoff patterns of pollutants into water will impact human health and pose challenges for water treatment facilities. Sea level rise could also threaten coastal drinking water supplies with the potential intrusion of saltwater flooding.

The report says the biggest water issues for the Midwest are adapting stormwater management systems and managing harmful algae blooms. Iowa is already familiar with floods produced by intense rainfall.  Algae blooms, fueled by nutrient-runoff from farm fields, will be further increased by rising temperatures.

Other water-related challenges detailed in the assessment include the deterioration of water infrastructure and managing water more strategically in the future.

 

On The Radio- Increasing global temperatures


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Kasey Dresser| November 26, 2018

This weeks segment looks at the effects of growing temperatures from 1901 to 2006. 

Transcript:

Average global temperatures will only continue increasing if nothing is done.

This is the Iowa Environmental Focus.

The average global temperature has increased between one point five and one point seven degrees Fahrenheit between 1901 and 2006. While a change of nearly two degrees over the course of a hundred years may not seem like much, the impact this change has is immense, and the consequences can be dire.

Warming in the Gulf of Mexico has increased rainfall especially in the Midwest, making flooding more widespread than in the past.

Heat waves are becoming hotter as well. A heat wave is defined as the five hottest days in a year. Iowa experienced a heat wave over the Memorial Day weekend this year, when temperatures averaged in the upper nineties.

As these changes occur, Iowans will need to invest more to adapt their buildings and storm water management systems to better prepare for more floods and the rising heat. The Iowa Climate Statement 2018 details some of these solutions.

For more information, visit iowa environmental focus dot org.

From the UI Center for Global and Regional Environmental Research, I’m Sara E Mason.

On the Radio- Green infrastructure key to keeping urban flooding at bay


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Green roofs are a type of green infrastructure (flickr).

Julia Poska | November 19, 2018

This week’s segment looks at flood mitigation approaches that incorporate nature into city design.

Transcript:

As Iowa’s extreme rain events intensify over time, flood management considerations will need to expand beyond river floodplains.

This is the Iowa Environmental Focus.

Floods commonly occur when rivers swell over their banks, but flooding can happen far from river systems, too.  Urban flooding occurs when drainage systems fail to move large amounts of storm water away from developed areas quickly.

According to the Iowa Climate Statement 2018, scientists forecast that daily rainfall in Iowa’s most extreme rain events will double by midcentury, meaning cities and towns will have even more water to manage.

One solution is to replace areas of impermeable concrete and asphalt with green infrastructure. These swaths of soil and vegetation absorb and slow down water to process it more naturally and reduce flooding.

Green infrastructure can be incorporated into sidewalks, buildings, backyards and even parking lots. Rain gardens, bio-swales, green roofs and more bring plants, soil and mulch into community design in attractive and helpful ways.

For more information, visit iowa-environmental-focus-dot-org.

From the UI Center for Global and Regional Environmental Research, I’m Sara E. Mason.

 

 

 

Hurricane Harvey worsened by Houston skyline


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The buildings of Houston made the floods it experienced last August more intense, a new study found (flickr). 

Julia Poska| November 16, 2018

Houston can partially blame the unprecedented flooding it experienced during Hurricane Harvey last year on its skyline. A new study co-authored by Gabriele Villarini, associate professor of civil and environmental engineering and director of IIHR-Hydroscience and Engineering at the University of Iowa, found that Houston’s topography exacerbated Harvey’s rainfall.

Researchers obtained data on rainfall and water discharge in Houston during the storm from various national agencies, and compared it to a computer model that simulated the same storm with a twist. In the model, the city of Houston was replaced with undeveloped farm fields to calculate the built environment’s effect on the storm’s behavior.

The analysis concluded that urban development in the Houston area increased the likelihood of intense fooding 21 times during that particular storm. In other words, if Houston were really an expanse of farmland instead of a city, less rain would have fallen.

“The buildings stop the air from being able to move forward, away from the ocean,” co-author Gabriel Vecchi from Princeton told NPR. “They sort of stop the air in that general area, and the air has nowhere to go but around the buildings, or up.”

Vecchi said when tall buildings push air farther upwards, the amount of atmospheric water vapor that condenses into rain increases. Houston’s skyline not only stalled the storm, but squeezed more rain out of it.