Guidance on the key themes andexpected outcomes

IPCC Expert Meeting on Short-Lived Climate Forcers
Geneva, Switzerland,
28 – 31 May 2018

Coverage of SLCF species
Following species will be covered in the discussion at Themes 1 and 2.
Some of them may be prioritized for further discussion at Theme 3.

Aerosols•••

Black Carbon
Organic Carbon
PM2.5

Precursors (ozone precursors and aerosol precursors)
••
•
•
•

NOxCO
NMVOC (including BVOC)
SO2NH3• Theme 1: Assessment of existing methodological framework,observation of atmospheric concentrations and methods toestimate emissions of SLCF

• Theme 2: Assessment of climate impacts of SLCF emissions• Theme 3: Suitability for IPCC to develop inventory methodologyfor SLCF

Theme 1: Assessment of existing methodological framework,observation of atmospheric concentrations and methods toestimate emissions of SLCF
Key questions:
How accurately can we monitor SLCF sources and emission trends, and link them toatmospheric concentrations?
On what SLCF species do emission quantification methodologies already exist, andat what scale (regional, national, sub-national, etc)?
Are they accessible, comprehensive, globally applicable, up-to-date?
Are new emission measurements by sources and species available?

What are the most significant knowledge gaps and uncertainties?
Is it necessary to develop new/improved guidance?
Is the current knowledge on emissions mature enough to support the developmentof new/improved guidance?
What new knowledge is expected to emerge in the coming years?

Theme 2: Assessment of climate impacts of SLCF emissions
Key questions:
What is the current scientific understanding of global radiative
forcing (via direct and indirect effects)?
What is the current scientific understanding of the local/regional
climate effects of SLCFs?
What emission metrics are available for SLCF?

What are the most significant knowledge gaps and uncertainties?
What new knowledge is expected to emerge in the comingyears?

Theme 3: Suitability for IPCC to develop inventory
methodology for SLCF
Key questions:
Which species of SLCF (and which sources) should beprioritised in the future work to develop inventory
methodologies? [Building on findings from themes 1and 2]
Is the IPCC the right organisation to develop theinventory methodologies?
How will these methodologies on SLCF relate to theexisting inventory methodologies on GHG (What kindof elements in the existing GHG inventory
methodology can or cannot be applied to SLCF?)

Scene-setting plenary
Day
1

Theme1(a)Theme1(b)Theme2(a)Theme2(b)Theme1(a)Theme1(b)Theme2(a)Theme2(b)PlenaryDay
2

PlenaryDay
3
Theme3(a)Day
4Theme3(b)Theme3(c)Closing plenary

Theme3(d)BOG participants willbe shuffled so thatboth TFI experts andWGI experts are ineach group.

Theme 1
BOGSession 1(Day 1)[160minutes]

••

•
•

BOGSession 2(Day 2)•••[180minutes]•How accurately can we monitor SLCF
sources and emission trends, and link themto atmospheric concentrations?
On what SLCF species do emission
quantification methodologies already exist,
and at what scale?
Are they accessible, comprehensive,globally applicable, up-to-date?
Are new emission measurements bysources and species available?

•What are the most significant knowledge
gaps and uncertainties?
Is it necessary to develop new/improved
guidance?
Is the current knowledge on emissionsmature enough to support the developmentof new/improved guidance?
What new knowledge is expected toemerge in the coming years?

•Outcome of Matrix (Sources x SLCF species) summarizing
BOGs above the conclusions on the key questions above.

Provisional conclusions on the necessity or
priority of development of inventory for each of
SLCF species, based on the conclusions on thekey questions above.

BOG
Session 3(Day 3)[230minutes]

Theme 2•••

Theme 3What is the current scientificunderstanding of global radiativeforcing (via direct and indirect effects)?
What emission metrics are available for
SLCF?

What is the current scientificunderstanding of the local/regional
climate effects of SLCFs?
What are the most significant
knowledge gaps and uncertainties?
What new knowledge is expected toemerge in the coming years?

Matrix (by SLCF species) summarizing theconclusions on the key questions above.
Provisional conclusions on the necessity or
priority of development of inventory for eachof SLCF species, based on the conclusions
on the key questions above.
•••

Which species of SLCF (and sources)
should be prioritised in the future todevelop inventory methodologies?
Is the IPCC the right organisation todevelop the inventory methodologies?
How will these methodologies on
SLCF relate to the existing inventory
methodologies on GHG?

Expected outcome: A meeting report• Maximum 50 pages• ~2-3 pages for summary and recommendations,• ~15 pages for the main part,• ~30 pages for the programme, list of participants and the compilation of responses to questions.

Expected outcome (continued)
Some outcome for WGI (in time for LAM1 end of June):• comments on the outline of Chapter 6 and on other partsof the report relevant to SLCFs– Ch2. Changing states of climate system (Natural and anthropogenic forcing;radiative forcing)– Ch3. Human influence in climate system (attribution)– Ch4 Future global climate (projection)– Ch6. Short lived climate forcers– Ch8. Water cycle (cloud-aerosol process)– Ch10. Link global to regional climate change (regional drivers, urban climatechanges)• State of knowledge about the SLCF effects