2015-11-02 Global Coupled Biogeochemistry Breakout Session Meeting Notes

A security person finally showed up and unlocked the door

• Scott Elliott (Unlicensed): LANL just hired Shanlin Wang, who is an expert on ocean carbon cycle modeling. That capability is expected to grow at LANL and complement the ongoing organic aerosol developments.
• George Hurtt (Unlicensed): Spatially gridded land-use/land-use change is a required forcing for all CMIP6 models. About ~15 CMIP6 models are expected to participate in a detailed land-use model inter comparison project (LUMIP, Hurtt co-Chair).
• Forrest M. Hoffman (Unlicensed): Will iESM be part of the V2 model? Will it have a separate set of experiments?
• Philip Cameron-Smith (Unlicensed): Methane is of interest at DOE. Sources include fracking,agriculture (rice, ruminants), and wetlands. (William Riley (Unlicensed) stated that slow permafrost melt probably won't be dramatic.)  There are many important science and policy questions around methane, so we should focus on the questions on the questions of most interest to DOE and which ACME is best positioned to answer.  Validating biospheric emission models is a challenge, so perhaps we could test biospheric methane by running model for a different time period (eg last glacial maximum).  William Riley (Unlicensed) noted that it can be a challenge to be confident of simulating precipitation and land cover.  Overall, methane is important for biospheric interactions and modeling CH₄ management policy may be useful for DOE.
• Susannah Burrows: Interested in aerosols, primary and secondary organic aerosols (POA and SOA). Previously worked on biological sources from land (e.g., fungal spores, etc.), but switched over to ocean sources. Her science goal is to improve the cloud-drop-number concentration that affects cloud formation and lifetime. In particular, the SOA treatment developed by Manish Shrivastava under ACES4BGC could be adopted and extended by ACME. SOA precursors, especially VOCs, are a large contributor to aerosol formation globally.
• Forrest M. Hoffman (Unlicensed): Terrestrial BVOCs are not yet part of the model carbon budget. Improving land BVOC representation is still an important goal and linked with work in GOAmazon and NGEE Tropics.
• Scott Elliott (Unlicensed): DOE should play a significant role in aerosol modeling research, leveraging its investments in ASR/ARM.
• Scott Elliott (Unlicensed): Coastlines offer an opportunity to link biogeochemical cycles across components. Riverine and estuarine BGC is an open science area with interesting interactions and influences on climate feedbacks.
• George Hurtt (Unlicensed): Nutrient runoff models are being used to study algal blooms and resulting dead zones in areas like the Gulf of Mexico, but not doing so on global scales or in the context of global ESMs.
• Scott Elliott (Unlicensed): In addition to the traditional carbon cycle, other chemical constituents are of interest, especially as they affect primary and secondary aerosols. CDIAC hosts a wealth of quality-controlled ocean data, not just on temperature, salinity, and alkalinity, but also on many other compounds of interest in open ocean and coastal zones. These data are important for constraining our newest model capabilities.
• George Hurtt (Unlicensed): Land management is an area that nobody else is focusing on, although it is on the same order as land cover change with respect to effects on climate. Examples include fertilizer application, irrigation, tillage practices, logging vs. clear-cuts. Global wood harvest now amounts to 1 PgC/y. There are many interactions with the atmosphere (e.g., N fertilizer volatilizes and affects atmospheric chemitry). Bioenergy is a part of this land management topic. There are also many ties to the water cycle since reservoirs and impoundments (by dams, etc.) represent human managed infrastructure not represented in models. This is of interest to Ruby Leung and her team at PNNL.
• Philip Cameron-Smith (Unlicensed) and Forrest M. Hoffman (Unlicensed): More dams are being considered and others are being raised to deal with both droughts and extreme rain events, which have complex ties with changes in climate.
• Xiaojuan Yang: Fire is another important topic, which has different impacts on nitrogen cycle and phosphorus cycle. While N is lost in gas form with fire, P does not volatilize. Instead, it remains on the ground and therefore provide additional available P for burned area or adjacent ecosystems.
• Forrest M. Hoffman (Unlicensed): We should work together to help design V2 experiments to answer questions related to cross-component coupled BGC. C⁴MIP experiments proposed for CMIP6 could be good candidates.
• Forrest M. Hoffman (Unlicensed) will initiate session meeting notes on Confluence, and participants should edit as desired.