Climate change report prepared for Austin predicts weather extremes

The first indications of how climate change likely will affect Austin in the coming decades are beginning to emerge. A just-completed report by City of Austin staff sets out some sobering scenarios of potential future conditions.

Extremes of heat, drought and floods that have occurred in the region in recent years are likely to become the new normal, the report concludes. Also, the average number of summer days over 100 degrees could more than triple. Dry periods will likely last longer. In addition, when it does rain, the downpours often will be heavier.

These and other changes could result in significant threats that city departments will need to address, according to the report. The threats include higher peak energy and water demands, less water availability, stress on vegetation and outdoor recreation, stress on outdoor workers, damage to pavements and roads, air and water quality concerns, and increased flood and fire risks, the report indicates.

Since 2007, city departments have been studying actions to reduce emissions from city operations to mitigate climate change. The new report assumes that climate change is inevitable and begins looking at how city departments, including Austin Energy, Austin Water Utility, Transportation, Public Works, Watershed Protection, Parks and Recreation, Fire, Austin/Travis County Health and Human Services, Homeland Security and Emergency Management, will need to adapt to future change. The report, titled Toward a Climate-Resilient Austin, responds to a resolution passed by the City Council last November.

“We are talking about the city being prepared,” said Zach Baumer, climate program manager at the city’s Office of Sustainability. “What we do now in infrastructure, whether it’s new (power) transformers or new roads or bridges or water lines, will have to be able to hold up to future conditions that are different from today.”

The key piece of the study was development of preliminary projections of what to expect in Austin from the changing climate, Baumer said. To do that, city staff enlisted the help of climate expert Dr. Katharine Hayhoe, director of the Climate Science Center at Texas Tech University and chief executive officer of a firm called ATMOS Research & Consulting. Hayhoe pulled national modeling data she developed for the recently published 2014 Third National Climate Assessment and scaled down the information to apply locally.

While Baumer cautioned that there are many uncertainties in making climate projections, he said the information provided a good starting point.

One major projection is that average temperatures will get higher in both summer and winter. For example, the current average summer high temperature of 94 degrees Fahrenheit could increase to 96 to 97 degrees over the next three decades and as high as 103 by the end of the century, according to the projections.

The number of summer days exceeding 100 degrees could increase from the current average of 13 to 15 to 20 days over the next three decades and between 25 and 50 in the 2041-2070 period. By the end of the century, the average number of summer days exceeding 100 degrees could be as many as 80, the projections show.

The number of warm summer nights (80 degrees or more), now rare, could average as many as 40 days in the 2041 to 2070 time period and as many as 85 days by the end of the century.

The total number of days per year without rain, now averaging 275, could be at 280 over the next three decades, and as many as 295 days by the end of the century, the projections show. In addition, the number of consecutive days without rain, currently averaging 52, could jump to 70 over the next three decades and as many as 75 days by the end of the century.

Baumer pointed out that city departments already have taken a number of steps, such as developing energy and water conservation programs, wildfire protection plans and a flood-warning system that will help deal with climate change.

“A lot of work has been done, so city departments are not being caught flat-footed here,” Baumer said.

Meanwhile, a resolution introduced by Council Member Chris Riley and approved unanimously by the Council last week will help ensure that climate-adaptation strategies become part of all departmental budgeting and planning efforts.

The report’s recommendations include developing more detailed climate projections, conducting more detailed assessments of where the city may be vulnerable to climate change and integrating climate-resilience strategies into current department planning. It also calls for the city to coordinate efforts with regional organizations including the Lower Colorado River Authority, the Electric Reliability Council of Texas, Capital Area Council of Governments, Capital Area Metropolitan Planning Organization, Texas Department of Transportation and Travis and surrounding counties.

The 26-page report may be found on the city’s Website.