• Climate & national securityNational security in the Fourth National Climate Assessment

    NCA4 vol. 2: “Climate change presents added risks to interconnected systems that are already exposed to a range of stressors such as aging and deteriorating infrastructure, land-use changes, and population growth. Extreme weather and climate-related impacts on one system can result in increased risks or failures in other critical systems, including water resources, food production and distribution, energy and transportation, public health, international trade, and national security. The full extent of climate change risks to interconnected systems, many of which span regional and national boundaries, is often greater than the sum of risks to individual sectors.”

  • FloodsUrban flooding disrupts local economies, public safety, housing equity

    Flooding caused by an increasing number of intense storms is a national challenge and significant source of economic loss, social disruption and housing inequality across the United States, says a new report. The first to assess the national scope and consequences of urban flooding, the report calls on the administration and Congress to bring together representatives from state, municipal and tribal governments, nongovernmental organizations, and the public to define responsibilities and implement a variety of actions at the local level.

  • Climate threatsU.S. gov.’s climate assessment: U.S. already suffering severe consequences of climate change

    The Fourth National Climate Assessment (NCA4)—a quadrennial report mandated by Congress since 1990—was released Friday. Thirteen federal agencies develop the NCA using the best available science to help the nation “understand, assess, predict and respond to” climate change. The 1,500-page report examines the climate and economic impacts U.S. residents could expect if drastic action is not taken to address climate change. The consequences of global warming for the U.S. economy, infrastructure, food production, water, and public health are already severe, as flooding, droughts, wildfires, rain storms, and hurricanes intensify. Unless warming is arrested, to consequences are only going to get worse.

  • WildfiresClimate change is driving wildfires, and not just in California

    By Jonathan Overpeck

    There are multiple reasons why wildfires are getting more severe and destructive, but climate change tops the list, notwithstanding claims to the contrary by President Donald Trump and Interior Secretary Ryan Zinke. According to the latest U.S. National Climate Assessment, released on 23 November, higher temperatures and earlier snowmelt are extending the fire season in western states. By 2050, according to the report, the area that burns yearly in the West could be two to six times larger than today. For climate scientists like me, there’s no longer any serious doubt that human activity – primarily burning fossil fuels – is causing the atmosphere to warm relentlessly. Climate change is driving a rapid increase in wildfire risk that has become a national problem. At the same time, healthy forests have become essential for the many valuable benefits they provide the nation and its people. Neither more effective forest management, nor curbing climate change alone will solve the growing wildfire problem, but together they can.

  • Grid protectionPredicting the impact of hackers, earthquakes -- and squirrels -- on the power grid

    What would it take for an entire American city to lose power? What circumstances and failures in the electrical grid’s infrastructure would lead to a dramatic, long-term blackout? And what weak points could utility companies invest in to help prevent a catastrophic shutdown?

  • DamsDam-breach simulation software helping communities plan for emergencies

    Two days after Hurricane Maria hit Puerto Rico, 70,000 residents in the vicinity of the Guajataca Dam were urged to evacuate as a precaution. Heavy rains were rapidly filling up the island’s 36 dams. Without clearer data, local authorities could only plan for the worst-case scenario. The Guajataca Dam, which holds more than 11 billion gallons of water, was on the verge of uncontrolled overflowing and could cause great devastation to the area downstream. These are challenges emergency managers face when they do not have reliable information.

  • Grid securityUsing game theory to quantify threats of cyberattacks on power grid

    Threat levels for cyberattacks on the power grid are usually labeled high, medium or low, but engineers say this is not good enough: Such judgements are too qualitative and too subjective. Could engineers incorporate scientific methods? Computer algorithms? And given that there are attackers and defenders – just like in a soccer match – could game theory be applied to help with risk assessment, attack-defense modeling and “what-if” contingency analysis that could help mitigate any attacks?

  • ResilienceStronger buildings could delay wildfire destruction, but not stop it

    Low humidity and strong winds in California mean that this month’s wildfires could strike again. Unfortunately, better building materials and planning can only offer so much protection, says an engineering expert.

  • Coastal perilNew sea-level rise and flood alert network launches

    The City of Imperial Beach is a low-lying coastal community south of San Diego that is one of the most vulnerable in California to sea-level rise. During periods of extreme high tides and winter swell, Imperial Beach experiences flooding that impacts residents, businesses and infrastructure. A new program, called Resilient Futures, will significantly upgrade its flood alert capabilities and better prepare for sea-level rise.

  • FloodsHouston's urban sprawl dramatically increased rainfall, flooding damage during Hurricane Harvey

    Houston’s urban landscape directly contributed to the torrential rainfall and deadly flooding experienced during Hurricane Harvey in August 2017, according to Princeton and University of Iowa researchers. The researchers report that Houston’s risk for extreme flooding during the hurricane — a category 4 storm that caused an estimated $125 billion in damage and killed 68 people — was 21 times greater due to urbanization.

  • Infrastructure protectionTechnology assesses bridge safety after powerful storms

    Hurricanes and heavy rains often cause strong, overflowing river currents that can damage critical infrastructure, such as bridges. For example, after Hurricane Katrina, many National Guard convoys loaded with aid did not drive on bridges for fear the bridges could not support the heavy trucks. To safely transport, they had to use roundabout roads or boats to reach Katrina survivors. Loose or loosening soil is often the culprit in weakening bridge stability. Thus, an instrument that can quickly assess the soil conditions around bridge pillars is a top priority.

  • Coastal perilMethods for protecting England’s coastal communities “not fit for purpose”

    In October 2018, a stark report suggested that current methods being used to protect England’s coastal communities are “not fit for purpose.” The Committee on Climate Change’s Managing the coast in a changing climate report showed that between 2005 and 2014, over 15,000 new buildings were built in coastal areas at significant risk of coastal flooding and/or erosion. Experts say that evidence suggests there should be far stricter controls on coastal developments.

  • EarthquakesAfter the next Big One: How will San Francisco’s skyscrapers fare?

    When Stanford civil engineers look at San Francisco’s skyline, they wonder: Will the city be ready if a major earthquake shakes those skyscrapers? It’s not primarily a question of whether all the towers will remain standing, though there are some concerns about the ones built more than 30 years ago. The more complicated question is this: If one or more high-rises suffers serious damage, how badly could that disrupt the rest of the city?

  • ResilienceBolstering resilience to withstand floods

    Historically, flooding is the most destructive natural disaster in this country. Facing this ever-growing threat, many wonder, “What can be done to protect life and property, reduce insurance claims, as well as help communities become more resilient?” DHS S&T has initiated multiple projects across the nation through its Flood Apex Program to offer an answer to this question.

  • Grid protectionProtecting the national electrical grid from space weather

    It’s not often geology and national security wind up in the same sentence. Most people don’t think about electrical power in connection to either the ground under their feet or solar flares overhead, but one researcher says that connection presents a clear and present risk that power utilities need to consider.