| 英文摘要: |
The global environment is changing rapidly. This century has seen 15 of the 16 warmest years since adequatethermometer records became available in the late 1800s; globally-averaged temperatures in 2015 shattered the previous record, which was set in 20141; and 2016 is on track to break the 2015 record2. Arctic seaice extent continues a dramatic, decades-long decline3. Many independent lines of evidence show a long-term warming trend driven by human activities, with cascading impacts that may outpace the ability of human and natural systems to adapt to change4.
The impacts of global climate change interact with existing and evolving socioeconomic and environmental stressors, creating complex challenges for society. New research confirms that climate change will heighten risks to human health, which are likely to disproportionately impact many already-disadvantaged communities and individuals5. More frequent and more intense extreme weather and climatic events are threatening food security, infrastructure, and livelihoods6. Communities around the world are facing rising seas and higher coastal flooding risk, impacts that will intensify over the coming decades7.
These impacts, separately and in combination, pose increasing risks to international stability and national security8. Of course, adaptation to, and mitigation of, climate change may also create certain long-term benefits and economic opportunities—such as building community resilience to extreme weather events and developing renewable energy technologies—but will require planning and investment. |
