8 May 2014 — A new report from the US government says climate change is impacting every region of the country and key sectors of the US economy and society, including human health, natural ecosystems and the built environment.

The Third National Climate Assessment was developed over the past four years as part of President Obama’s Climate Action Plan, and was contributed to by hundreds of climate scientists and technical experts.

The report detailed changes already happening now in the country, including:

  • Northeast: communities “are affected by heat waves, more extreme precipitation events, and coastal flooding due to sea level rise and storm surge”.
  • Southeast and Caribbean: “Decreased water availability, exacerbated by population growth and land-use change, causes increased competition for water in this region. There are also increased risks associated with extreme events such as hurricanes.”
  • Midwest: “Longer growing seasons and rising carbon dioxide levels increase yields of some crops, although these benefits have already been offset in some instances by occurrence of extreme events such as heat waves, droughts and floods.”
  • Great Plains: “Rising temperatures lead to increased demand for water and energy and impacts on agricultural practices.”
  • Southwest: “Drought and increased warming foster wildfires and increased competition for scarce water resources for people and ecosystems.”
  • Northwest: “Changes in the timing of streamflow related to earlier snowmelt reduce the supply of water in summer, causing far-reaching ecological and socioeconomic consequences.”
  • Alaska: “Rapidly receding summer sea ice, shrinking glaciers, and thawing permafrost cause damage to infrastructure and major changes to ecosystems. Impacts on Alaska Native communities increase.”
  • Hawaii and Pacific Islands: “Increasingly constrained freshwater supplies, coupled with increased temperatures, stress both people and ecosystems and decrease food and water security.”
  • Coasts: “Coastal lifelines, such as water supply infrastructure and evacuation routes are increasingly vulnerable to higher sea levels and storm surges, inland flooding, and other climate-related changes.”

The report is a wake-up call for Australia and challenges the Australian federal government to face reality and join with its most important ally in tackling the global issues coming from climate change.

While President Barack Obama goes on a roadshow to deal with sceptics, the key questions have shifted from whether climate change is occurring to whether society can manage the challenges.

Urban vulnerabilities

The report found that urban dwellers were particularly vulnerable to disruptions in essential infrastructure services, due to the systems being dependent on one another.

“For example, electricity is essential to multiple systems, and a failure in the electrical grid can affect water treatment, transportation services, and public health,” the report states. “These infrastructure systems – lifelines to millions – will continue to be affected by various climate-related events and processes.”

The report noted an event in New York City in 2007 where intense rainfall during the morning commute stranded 2.5 million riders, shutting down much of the subway system, and severely disrupting the city’s bus system.,

“The storm’s impact was unprecedented and, coupled with two other major system disruptions that occurred in 2004 and 2007, became the impetus for a full-scale assessment and review of transit procedures and policy in response to climate change.”

The report said that city preparedness for climate change included planning for ways in which infrastructure and buildings would be affected.

“Cities are engaged in activities ranging from education and outreach to assessment, planning, and implementation, with 48 per cent reporting that they are in the preliminary planning and discussion phases,” the report stated.