• Climate threatsGreenhouse gas levels in atmosphere break another record

    Levels of heat-trapping greenhouse gases in the atmosphere have reached another new record high, according to a report issued on Thursday by the United Nations weather agency, which reveals that there is no sign of reversal of this trend, responsible for climate change, sea level rise, ocean acidification and extreme weather.

  • Climate threatsCarbon emissions from advanced economies to rise in 2018 for first time in five years

    The world’s advanced economies will see an uptick in their carbon dioxide emissions this year, bucking a five year-long decline, according to the International Energy Agency (IEA). Based on the latest available energy data, energy-related CO2 emissions in North America, the European Union and other advanced economies in Asia Pacific grew, as higher oil and gas use more than offset declining coal consumption. As a result, the IEA expects CO2 emissions in these economies to increase by around 0.5 percent in 2018.

  • Climate threatsWorld simply “not on track” to slow climate change this year: UN weather agency

    The 20 warmest years on record have been in the past 22 years, with the top four in the past four years. “It is worth repeating once again that we are the first generation to fully understand climate change and the last generation to be able to do something about it,” Professor Petteri Taalas, Secretary-General of the World Meteorological Organization (WMO), said.

  • 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.

  • GeoengineeringAnti-global warming atmospheric spraying program: Could it work?

    A program to reduce Earth’s heat capture by injecting aerosols into the atmosphere from high-altitude aircraft is possible, but unreasonably costly with current technology, and would be unlikely to remain secret. Those are the key findings of new research which looked at the capabilities and costs of various methods of delivering sulphates into the lower stratosphere, known as stratospheric aerosol injection (SAI).

  • 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.

  • Public healthWildfire smoke is becoming a nationwide health threat

    By Richard E. Peltier

    The impacts of recent forest fires in California reach well beyond the burned areas. Smoke from the Camp Fire created hazardous air quality conditions in San Francisco, more than 170 miles to the southwest – but it didn’t stop there. Cross-country winds carried it across the United States, creating hazy conditions in locations as far east as Philadelphia. As an air pollution exposure scientist, I worry about the extreme levels of air pollution that rise from these fires and affect many people across great distances.

  • 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.

  • California firesBetter forest management won’t end wildfires, but it can reduce the risks – here’s how

    By Courtney Schultz and Cassandra Moseley

    President Donald Trump’s recent comments blaming forest managers for catastrophic California wildfires have been met with outrage and ridicule from the wildland fire and forestry community. Not only were these remarks insensitive to the humanitarian crisis unfolding in California – they also reflected a muddled understanding of the interactions between wildfire and forest management. As scientists who study forest policy and community-based collaboration, here is how we understand this relationship.

  • California firesThe bitter lesson of the Californian fires

    By David Bowman

    California is burning, again. Dozens of peoples have been killed and thousands of buildings destroyed in several fires, the most destructive in the state’s history. The California fires are just the most recent in a series of major wildfires, including fires in Greece in July this year that killed 99 people, Portugal and Chile in 2017, and Australia. Why do wildfires seem to be escalating? Despite president Donald Trump’s tweet that the California fires were caused by “gross mismanagement” of forests, the answer is more complex, nuanced, and alarming.

  • 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.