Carbon Cycle-Climate Feedbacks in Post-Paris World

• Paris calls for stabilizing climate at 1.5C
• Reduce emissions, maintain and manage sinks, stay within remaining carbon budget (RCB)

Schimel, 2024, Annual Reviews

3 Major Challenges Post-Paris Take stock of carbon (e.g., for Global Stocktake) Track change in carbon stock (i.e., feedbacks to reduced CO2 growth rate, warmer and more extreme climate) Predict future change in carbon stock (i.e., predict how land and ocean sinks will respond to stabilized climate)

Goals of Carbon Workshop Series

Three “Pre-Decadal” carbon workshops over the next 1.5 years to establish a community agreed upon path for leveraging existing and future tools to improve our understanding of, and ability to predict, carbon-climate feedbacks over the next several decades under more extreme climate and changing emissions.

Main Goals:

1. Identify outstanding challenges that stand in the way of progress
2. Identify gaps that exist with respect to knowledge and data
3. Identify opportunities for progress including potential ways to fill gaps with data

Three workshops are organized around the following themes:

• Stock of Stocks: Establish state of the art for assessment of carbon fluxes and stocks; identify key remaining gaps and uncertainties across different sectors (land, ocean, urban, agricultural, forests, critical regions).
• Delta Stocks (Feedbacks): Determine how stocks are responding to changing emissions and climate; identify gaps/uncertainties in our ability to track and understand feedbacks.
• Predicting Feedbacks: Establish state of the art for combining models and observations to constrain predictions, and identify how new observations and data assimilation approaches can provide more robust and realistic predictions, especially under increasing extremes and reduced emissions.

Each workshop is to be followed by a community-led position paper, summarizing challenges, gaps, and opportunities.

Workshop 1: Taking Stock of Stocks
Tracking GHG Emissions and Removals for the Global Stocktake

Stock of Stocks Workshop Themes

Theme 1: GHG Information for Stocktake

• Engagement with political entities
• Top-down approaches
• Machine learning and upscaling
• Carbon Cycle Data Assimilation Systems
• GHG Center

Theme 2: Reconciling Observational Approaches and Models

• Benchmarking
• RECAPP
• GEOS-GHG

Theme 3: Key GHG Sectors

• Sectors: Urban, Forests, Agriculture
• Critical Regions / Tipping Points: Arcitc, Ocean, Coastal, Tropics, Drylands

Theme 4: Future GHG Observing Systems

• Carbon-I: Frankenberg
• Hyperspectral: Serbin, Schimel
• Airborne: Miller

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Meeting Logistics

Place:
383 Hill Annex, California Institute of Technology, Pasadena, CA, USA

Dates:
September 23-24, 2024, 8:30am – 5:00pm, Pacific Time Zone (PT), exact times TBC.

RSVP:
Invitation only

Format:
In-person

Travel tips:

• By air:
  (1) Los Angeles International airport (LAX): you can then reach Pasadena by taxi/rideshare/rental car (~45min-1h), or public transport (shuttle to downtown LA + metro to Pasadena, ~1h30min).
  (2) Burbank Airport (BUR); you can then reach Pasadena by taxi/rideshare/rental car in ~25min.
• By train:
  Amtrak will get you to Los Angeles Union station, which is about 20min by metro or taxi/rideshare from Pasadena

Accommodation tips:

There are a number of hotel or homestay options (e.g. Airbnb) within the vicinity of Caltech or old town Pasadena. Some advantages of staying in old town Pasadena include (i) walkable & pleasant, and (ii) cafes, restaurants etc are all in walking distance, (iii) Caltech is attainable on foot or by public transport (Old town ~20-30min walk or short bus ride away from Caltech).

Format:

Each of four themes gets approximately half a day (negotiable)

• Short talks and Q/A for each speaker (<10 min)
• Parallel breakouts: Groups of 5-10 (~1 hour)
• Breakout reports and discussion (~30-60 min)