Third National Climate Assessment Unequivocal about Climate Change

“Evidence
for climate change abounds, from the top of the atmosphere to the depths of the
oceans,” reads a draft of the Third National Climate Assessment, published
for public review by the U.S. Global Change Research Program on Friday. 

The draft study is unequivocal about the state of climate
change: it is already affecting Americans and it is primarily driven by human
activity.  According to an excerpt
from the study’s executive summary:

Climate
change is already affecting the American people. Certain types of weather events
have become more frequent and/or intense, including heat waves, heavy downpours,
and, in some regions, floods and droughts. Sea level is rising, oceans are becoming
more acidic, and glaciers and arctic sea ice are melting. These changes are part
of the pattern of global climate change, which is primarily driven by human activity. 

The congressionally mandated study – a result of the Global
Change Research Act of 1990 – is intended to provide policymakers with a better
understanding of the impact of climate change on U.S interests – from human
health and biodiversity to energy production and transportation. The assessment
is required every four years, but in practice has been more ad hoc. (This
assessment is the third one since the 1990 act was passed by congress.)

The study also provides useful insights to national security
and foreign policy practitioners charged with navigating the changing global
climate landscape and making sense of the impact on U.S. interests. While the
study explores areas for mitigating climate change – that is, reducing
greenhouse gas emissions that are adding to climate change – it also emphasizes
adaptation to changes that are already locked in as a result of decades of
emissions increases. According to the study, “Proactively preparing for climate
change can reduce impacts, while also facilitating a more rapid and efficient
response to changes as they happen.” 

The draft study is worth a closer examination than we can provide here on the blog. Read the full report here.

read more

www.cnas.org