# Presentation: 502684

## Atmospheric Composition Summary

**Strategic Plan for the Climate Change Science Program**

*Planning Workshop for Scientists and Stakeholders*
*December 3-5, 2002  Washington, DC*

- Daniel L. Albritton
- NOAA Aeronomy Laboratory
- Boulder, Colorado

- Phil DeCola
- NASA Headquarters
- Washington, DC

- Chapter Co-Chairs

**Interagency Group:**** *****DOE, EPA*****, *****NASA, NAVY, NIH, NOAA, NSF, USDA ***
- D. Anderson, R. Ferek, J. Gleason, M. Grant, T. Keating, D. Kruger, J. Levy,
- M. Kurylo,** **P. Lunn,** **J. Moyers, A. Schmoltner, H. Tyrrell, D. Winner

## Today’s Summary

- • _A little background_
- • _Current perspectives and challenges_
- • _Major research questions, activities, and payoffs_
- • _Overall research approach_
- • _Partners_
- • _Products_
- • _The shape of the future_

- > Where atmospheric composition fits in
- > Some key characteristics
- > Radiative forcing/climate
- > Ozone layer recovery
- > Multiple environmental issues
- > Five foci
- > For each, examples:
- 	• *key questions*
- 	• *research*
- 	• *payoff*
- > What _types_ of activities
- > And why
- > National and international
- > Next several years
- > Some special challenges

##  Much of the coupling between incoming solar energy and the atmosphere occurs via trace constituents

- (H2O), CO2, CFCs, CH4, ozone, aerosols ...

_**Where Atmospheric Composition Fits In**_

-  **Much of the **_**coupling**_** between incoming **_**solar energy**_** and the **_**atmosphere**_** occurs via trace constituents**

-  **This coupling gives rise to **_**major environmental issues**_

-  **Changes in **_**trace constituents**_** arise largely from **_**human activities**_** (surface emissions sources)**

_**Bottom line:**__** Understanding atmospheric composition**_** is a key **_**first step**_** in:**
**• ****Characterizing the human influence **
**• ****Constructing scenarios/predictions for consideration as options**
**• ****Identifying “win-win” choices in addressing multiple issues: air quality and climate**

**Enhanced Greenhouse Effect**

**Ozone-Layer Depletion**

**Regional Air Quality**

## Some Key Characteristics

##    Current Perspectives and Challenges: 

- • _Long and short_ residence times
- • _Global and regional_ scales

**   **_**Current Perspectives and Challenges:**_** **
_**A. **__**Radiative Forcing of the Climate System**_

- IPCC, 2001.

## Current Perspective and Challenges:  

- Space-based remote-sensing observations compared with UNEP baseline emissions scenario time-lagged 5.3 years

- Ground-based remote-sensing

- Ground-based in-situ sampling

- • Observations consistent with emissions decline: _Compliance evaluation_
- • Ozone-climate coupling influences _long-term recovery_
- • _New issues arising_ (*e.g., very short-lived gases*)

_**Current Perspective and Challenges:**_**  **
**         **_**B. **__**Ozone Layer Recovery**_

- Stratospheric Chlorine Abundance

## Current Perspectives and Challenges:

- • Research is beginning to address _multiple issues_
-     (*e.g., aerosols, climate, and air quality*)
- • Characterization of _sign/magnitude_ of win/win or win/lose
-      multi-issue strategies is new policy relevant information

- ACE-ASIA Program

_**Current Perspectives and Challenges:**_
**    **_**C. **__**Multiple environmental issues**_

## Major Atmospheric-Composition Research Foci

- • **Ozone Layer**
**     ****Recovery**

- • **Chemically-**
**     ****Active**
**     ****Greenhouse**
**     ****Gases**

- • **Multiple Environmental **
**     ****Issues**

- • **Regional-**
**     ****Global**
**     ****Couplings**

- • **Aerosols**

_**Major Atmospheric-Composition Research Foci**_

## The Scientific Foci:  Brief Looks

_**The Scientific Foci:  Brief Looks**_

## Slide 10

## Overall Research Approach

**Modeling**

**Process**
**Studies**

**Monitoring**

*Diagnostics*
*&*
*Prognostics*

*Distributions et al.:*
*Trends & Variance*

*Causal*
*Linkages*

**A**
**S**
**S**
**E**
**S**
**S**
**M**
**E**
**N**
**T**
**S**

**Information**
**Customers**

*Decision*
*Support*
*Information*

*Governments,*
*Industries,*
*Public*

## Linkages With the Information Customers:A Series of Assessments of Understanding and Scenarios

**2004**

**2006**

**2003**

**2005**

**2002**

**2000**

**2001**

**2007**

-     IPCC _Third_
- Assessment Report

-     UNEP/WMO 2002
- Ozone Layer Assessment

-     IPCC _Fourth_
- Assessment Report

- We Are
- Here

-     U.S.
- Assessment
- Products:
- Planning
- Underway

-     UNEP/WMO
- 2006
- Ozone Layer
- Assessment

- 

- 

*Key Factors in the Near-Term*
*Research Planning*

## Longer-Term Timeline: Key Characteristics

- • Maintain and build _monitoring capability_
- 		> satellite instruments
- 		> integrated (*and persisting!*) observing sites
- • Development of _new measurement capability_
- • Construction of _science-quality datasets_ for atmospheric change parameters
- • Expanded *international* partnerships

## National and International Partners: Examples

## Key Near-Term (2 - 4 years) Products and Payoffs: 

**                           **_**A Few Examples**_

## The Shape of the Future

- How to ...

##               Appendix:

_**A. Major Research Questions**_** **

- Scientific foci:

- •  Aerosols
- •  Chemically Active Greenhouse Gases
- •  Regional - Global Couplings
- •  Ozone Layer Recovery
- •  Multiple Environmental Issues

- For each:  Major research questions
-  	Task & Payoff: Examples

_**B. Examples of Key Near-Term**_
**        **_**Products and Payoffs**_

## Aerosols

_**Question 1:**_* *What are the climate-relevant chemical and radiative properties, and spatial and temporal distributions, of human-caused and naturally occurring aerosols?

- 1. Develop an observationally vetted climatology of aerosols (including black carbon) distribution and properties for one or two regions, including North America, through in-situ airborne, ground-based, and satellite observations.  (Coupling to the regional air quality issue of USA)
*	**Will provide an observationally vetted database for calculating the climate forcing by aerosols and enable comparison of this forcing with those for long-lived greenhouse gases.*
- 2. Work towards retrieval of global aerosol optical depth, as a function of location and time, from ground and space based observations, augmented by in-situ observations.
*	**Will provide a key step in the long-term derivation of the aerosols from space, ground-truthing space measurements, and data for use in models.*
*	**Will facilitate assessment and improvements in the skill of global models to simulate aerosol distributions and affects**.*

## 3. Carry out focused attempts at better quantification of the first indirect effect (Twomey effect) through process studies and detailed microphysical and cloud modeling.

*	**Will provide observationally derived estimates of one of the important indirect effects in the climate forcing and place better bounds on uncertainties of indirect effects.*
- 4. Carry out studies to connect chemical composition of aerosols with optical properties and, ice and cloud nucleation abilities of aerosols (including black carbon) and source of the precursors. (Coupling to the regional air quality issue of USA)
*	**Will help quantify the connection of emissions to the various radiative impacts of aerosols.*

## Chemically Active Greenhouse Gases

_**Chemically Active Greenhouse Gases**_

## Slide 21

## Regional              Global phenomena

_**Regional              Global phenomena**_

## Ozone Layer Recovery

_**Ozone Layer Recovery**_

## Multiple Environmental Issues

_**Multiple Environmental Issues**_

## Examples of Key Near-Term Products and Payoffs

_**Examples of Key Near-Term Products and Payoffs**_

## Slide 26