Track: C4. Policy Perspectives on Accelerating Carbon Emission Reduction
Background/Objectives
Arctic sea ice is a critical component of the global climate system because of its contributions to Earth’s reflectivity (albedo) and potential influence on global weather patterns. It is also one of the fastest changing systems on the planet. The loss of summer sea ice to date has already had profound impacts on the Arctic region, its ecosystems and people, the global climate system, and the broader ocean.
- The Arctic region has warmed three to four times faster than the global average1-4. The faster pace of warming in the Arctic relative to the global average is known as Arctic Amplification.
- Increases in air and sea temperature in the Arctic have led to at least a 50% decline in the extent of Arctic summer sea ice over the last four decades5-7. Since 1979, thicker multi-year sea ice at least five years old has decreased by 90%6. Thicker multi-year ice has a higher albedo than thinner new ice and is also less vulnerable to melting8.
- Summer sea ice is expected to disappear by the middle of this century (under all emissions trajectories9), if not earlier10-11.
What are the climate impacts?
- The loss of summer sea ice and snow has amplified warming in the Arctic due to a decrease in albedo (reflectance of incoming solar radiation)6. This causes an energy imbalance in the Arctic (and on the planet) as darker surfaces trap incoming solar energy rather than reflecting it as sea ice does.
- The excess heat trapped as a result of the current Arctic albedo decrease accounts for about 20% of the total excess heat associated with greenhouse gas emissions into our atmosphere since 197912.
- Global climate models estimate that the complete loss of summer sea ice will cause additional warming in the Arctic of >1.5°C and 0.19°C13 averaged across the globe.
Approach/Activities
The only permanent way to stop the loss of Arctic sea ice and ultimately to rebuild it is to reduce atmospheric concentrations of greenhouse gases. However, given the very slow pace of progress in global decarbonization, and the near-term risks to humanity and nature of continuing ice loss, several other ideas and technologies have been discussed as approaches to slow down the loss of sea ice and even to potentially rebuild it.
To better understand whether any of these pathways may work, and effectively “buy time” for deep decarbonization and carbon removal to more durably stem global heating, Ocean Visions is undertaking a deep assessment of all potential approaches to slowing the loss of and rebuilding Arctic sea ice.
This assessment will be published in a digital, interactive road map when it is completed. The map will review the current state and potential of relevant technology pathways, social and environmental risks and co-benefits of such technologies, policy and governance considerations, and the knowledge gaps that need attention to further evaluate the tools and interventions. The map will also identify a set of first-order priorities for additional research, development, and potential testing. In developing this content, Ocean Visions is engaging with experts and stakeholders from a diversity of backgrounds and perspectives.
Results/Lessons Learned
To date, the mapping process has engaged >80 individuals from 13 countries and identified 26 pathways across five broad categories: pollution management, solar radiation management, protection, ice management, and surface albedo modification. The approaches span various levels of technology and societal readiness, and their impact spans from local to global. We will be able to talk about these in greater detail at the time of the event.
Once finalized, the road map will be available on an interactive web platform alongside other Ocean Visions’ road maps for ocean-based climate solutions (www.oceanvisions.org/roadmaps). Previous maps have facilitated collaborative work on key priorities and are regularly updated as advances emerge in science, technology, governance, policy, and ethics.