Today, the U.S. Global Change Research Program, a government-supervised coordinating body for scientific research, released the National Climate Assessment (NCA), a comprehensive summary of extant scientific research, conclusively demonstrating the wide-ranging impacts climate change is already having on the population and economy of the United States. The NCA serves as a domestic equivalent to the United Nation’s Intergovernmental Panel on Climate Change’s semi-regular Assessment Reports.

The report documents in exacting detail that global temperatures have been growing steadily since the Industrial Revolution, with a particular acceleration since 1970. The existing research demonstrates beyond a shadow of a doubt that these warming patterns are due to human economic activity, namely the burning of fossil fuels for electricity generation and transportation, and land use patterns, particularly deforestation and agricultural practices. The effects reach into virtually every sector of the U.S. economy: human health, agriculture and fishing, infrastructure, and coastal living. (You can read great reportage on the entire assessment from the ThinkProgress, Los Angeles Times; Mother Jones/Guardian, The New York Times, and Huffington Post).

The most important takeaway from the report is contained in these forty words addressing how we should respond:

Planning for adaptation (to address and prepare for impacts) and mitigation (to reduce future climate change, for example by cutting emissions) is becoming more widespread, but current implementation efforts are insufficient to avoid increasingly negative social, environmental, and economic consequences.

In other words, our current policy trajectory is not nearly radical enough to fully reverse the course we are on. The various stakeholders (federal, state, and local governments, business, non-governmental organizations, and community groups) have yet to overcome the very serious implementation barriers to robust adaptation and mitigation barriers. Generally, these barriers include financing, political will, and the unpredictable nature of anticipating how exactly climate change will manifest itself at the local level.

The lack of political will is a particularly egregious: as the NCA notes, the U.S. lacks comprehensive national climate legislation. Instead, we have a patchwork quilt of state-led efforts, such as California’s cap-and-trade or the Regional Greenhouse Gas Initiative, as well as renewable energy and energy efficiency standards, some of which are voluntary. The lack of appetite in Congress is the central reason the Obama administration is being so aggressive with its own regulatory authority, principally through the Environmental Protection Agency.

The most efficient single step that the United States could take to halt climate change is a nationwide price on carbon, but that is simply not in the cards. That is a critical deficiency, as the NCA makes abundantly clear.