# Presentation: 216433

## Global aerosol forecasting and data assimilation

- Overview, Work Plan and Progress Update
- Sarah Lu

## Key mechanisms for utilizing satellite observations
Aerosols affect the interpretation of satellite data for atmospheric, land, and ocean applications

Potential for improvements in forecast accuracy
Radiation: Aerosols affects surface radiation both directly (via scattering and absorption) and indirectly (through cloud-radiation interaction)
Hurricane: Dust-laden Saharan air layer reduces occurrence of deep convection and suppresses tropical cyclone activities

Impacts on climate, human health, ecosystem, and visibility
Regional air quality: Aerosols (lateral and upper) boundary conditions are needed for planned PM prediction
Aviation and visibility: Emissions from large wild fires affect aviation route planning and visibility forecasts

**Aerosols affect the interpretation of satellite data for atmospheric, land, and ocean applications**
**Potential for improvements in forecast accuracy**
**Radiation:**** Aerosols affects surface radiation both directly (via scattering and absorption) and indirectly (through cloud-radiation interaction)**
**Hurricane:**** Dust-laden Saharan air layer reduces occurrence of deep convection and suppresses tropical cyclone activities**
**Impacts on climate, human health, ecosystem, and visibility**
**Regional air quality:**** Aerosols (lateral and upper) boundary conditions are needed for planned PM prediction**
**Aviation and visibility:**** Emissions from large wild fires affect aviation route planning and visibility forecasts**

**Rationale**

## OVERVIEW
Create an integrated operational system for forecasting and monitoring the atmospheric chemistry and dynamics

GOAL
Generate optimal (accurate and affordable) description of global distribution of atmospheric aerosols
Provide improved air-chemistry forecasts, through improved exploitation of satellite data

APPROACH
Incorporate prognostic aerosols in GFS
Assimilate aerosol measurements (AOD and then radiance) in GSI
Leverage common modeling framework and shared software development (JCSDA and ESMF)

**Create an integrated operational system for ****forecasting and monitoring**** the atmospheric chemistry and dynamics**
**GOAL**
**Generate optimal ****(accurate and affordable)**** description of global distribution of atmospheric aerosols**
**Provide improved air-chemistry forecasts, through improved exploitation of ****satellite data**
**APPROACH**
**Incorporate prognostic aerosols in GFS**
**Assimilate aerosol measurements (AOD and then radiance) in GSI**
**Leverage common modeling framework and shared software development ****(JCSDA and ESMF)**

**NCEP global aerosol forecasting ****and data assimilation**** **

## ESMF Component Framework

- Mark Iredell

**Atmosphere**

**ATM**
**Dynamics**

**ATM**
**Physics**

**Notes:**
Dynamics and physics are developed by mostly different groups.

## Depends on surface winds

**Biomass burning**
**Biofuel**
**Anthropogenic, other**
**Biogenic OC**

**Anthropogenic**
**Biomass burning**
**Oxidation of SO****2**** w/ OH and **
**Aqueous reaction with H****2****O****2**

**Anthropogenic**
**Biomass burning**
**Oxidation of DMS w/ OH and NO****3**

**Depends on surface winds**

**Topographic Source**
**4 size classes 0.1 – 6 ****μ****m radius**

**Improved representation of **
**sub-micron particles**
**5 size classes 0.03 – 10 ****μ****m dry radius**

**Based on measured sea **
**surface concentration**

**Dust**

**Sea salt**

**DMS**

**SO****2**

**SO****4**

**BC/OC**

**Sources**

**Chemistry/**
**Transformation**

**Sinks**

**Swelling by RH**

**Oxidation to SO****2**

**Oxidation to SO****4**

**Fractionation of **
**Hydrophobic & **
**Hydrophilic **
**Components**

**Sedimentation**
**Dry deposition**
**Wet removal**

**Chemistry**

**Chemistry**
**Dry deposition**
**Wet removal**

**Dry deposition**
**Wet removal**

**Dry deposition**
**Wet removal**
**(hydrophilic only)**

- Arlindo da Silva (GMAO)

## ESMF Component Framework

- Mark Iredell

**Atmosphere**

**ATM**
**Dynamics**

**ATM**
**Physics**

**GOCART**
**GridComp**

**SS**

**SU**

**DU**

**OC/BC**

**Notes:**
Dynamics and physics are developed by mostly different groups.

## Prototype aerosol forecasting system

**GFS forecast from T0**

**GOCART forecast from T0**

**GOCART forecast from T+**

**GFS forecast from T+**

**Communication**** ****of dynamics info**

**Communication of chemical info**

## BASELINE CONDITION
Climatology-derived aerosol distributions are used in the GFS
Background aerosol conditions are assumed in the GDAS radiative transfer scheme

SHORTCOMING
The effects of aerosols on radiation, clouds, and convection are poorly constrained in the GFS
The effects of aerosol attenuation on radiance assimilation are yet to be quantified in the GDAS

PROPOSED ENHANCEMENT
Global aerosol products will improve the representation of aerosol distribution and variations within the GFS/GDAS system

**Climatology-derived aerosol distributions are used in the GFS**
**Background aerosol conditions are assumed in the GDAS radiative transfer scheme**
**SHORTCOMING**
**The effects of aerosols on radiation, clouds, and convection are poorly constrained in the GFS**
**The effects of aerosol attenuation on radiance assimilation are yet to be quantified in the GDAS**
**PROPOSED ENHANCEMENT**
**Global aerosol products will improve the representation of aerosol distribution and variations within the GFS/GDAS system**

**NOAA medium range weather forecasts**

## Aerosol distributions vary significantly 

**Sulfate AOT****  **

**Dust AOT**

**Aerosol distributions vary significantly **
**from day to day**

**Apr 02, ‘01**

**Apr 12, ‘01**

**Mian Chin (GSFC)**

## Aerosol vertical distribution changes:

**April**

**September**

**Aerosol extinction at 550 nm**

**Mian Chin (GSFC)**

## Aerosol composition changes with locations/seasons:

**April**

**September**

**Mian Chin (GSFC)**

## BASELINE CONDITION
Default static boundary conditions are used for PM air quality predictions

SHORTCOMING
The use of static boundary conditions cannot account for the impact of long-range aerosol transport on PM loading over the US

PROPOSED ENHANCEMENT
Global aerosol products will provide improved PM lateral boundary conditions for the AQF system and, consequently, improve PM air quality forecasts

**Default static boundary conditions are used for PM air quality predictions**
**SHORTCOMING**
**The use of static boundary conditions cannot account for the impact of ****long-range aerosol transport**** on PM loading over the US**
**PROPOSED ENHANCEMENT**
**Global aerosol products will provide improved PM lateral boundary conditions for the AQF system and, consequently, improve PM air quality forecasts**

**NOAA air quality forecasts**

## Dust Evolution and Trans-Pacific Transport

**Mian Chin (GSFC)**

## How do the “foreign sources” affect “native” air quality?

**Sulfate over North America:**
**Most sulfate stays in the boundary layer**
**Pollution from Asia can travel around the hemisphere at higher altitudes above BL**
**European pollution makes its way over N. America at higher latitudes**
**In the BL over North America, most sulfate is  from is own regional source**

**East**** ****Coast**

**West Coast**

**Altitude (km)**

**Altitude (km)**

**Altitude (km)**

**Altitude (km)**

**SO****4****=**
**μg m****-3**

**% from**
**Asia**

**% from**
**Europ**

**% from**
**N America**

**Mian Chin (GSFC)**

## How do the “foreign sources” affect “native” air quality?

**How do the “foreign sources” affect “native” air quality?**

**Dust Over North America:**
**Dust plume has broad vertical extension above the BL**
**Most dust below 6 – 7 km is from Asia**
**Dust from the Middle East contributes to about 10% dust loading**
**African dust is an important contributor to the dust level in the tropics and at high altitudes above 6 – 7 km**

**East Coast**

**West Coast**

**Altitude (km)**

**Altitude (km)**

**Altitude (km)**

**Altitude (km)**

**Dust**
**μg m****-3**

**% from**
**Asia**

**% from**
**Middle East**

**% from**
**Africa**

**Mian Chin (GSFC)**

## Adoption of GOCART modeling component
Modification of GFS radiation module
Extension of GFS tracer capability to include aerosols
Development of ESMF interface for coupling GOCART and GFS
Deliverable: GFS-GOCART simulated aerosol products
Utilization of MODIS/OMI measurements
Incorporation of MODIS/OMI into NCEP operational data tank
Evaluation and error analysis based on AODs and radiance
Deliverable: MODIS/OMI calibrated aerosol products 
Integration of global aerosol products in NOAA decision support
Interface global aerosol products with CMAQ-NAM
Couple global aerosol products with GFS/GSI
Adopt global aerosol products in SST analysis system
Deliverable: Benchmarking of improvements in NOAA decision support 
Research-to-operation transition
Optimize the configuration to fit operational resource and time constraints
Manage the logistics for operational implementation
Deliverable: Operation implementation

**Modification of GFS radiation module**
**Extension of GFS tracer capability to include aerosols**
**Development of ESMF interface for coupling GOCART and GFS**
**Deliverable: GFS-GOCART simulated aerosol**** ****products**
**Utilization of MODIS/OMI measurements**
**Incorporation of MODIS/OMI into NCEP operational data tank**
**Evaluation and error analysis based on AODs and radiance**
**Deliverable: MODIS/OMI calibrated aerosol**** ****products**** **
**Integration of global aerosol products in NOAA decision support**
**Interface global aerosol products with CMAQ-NAM**
**Couple global aerosol products with GFS/GSI**
**Adopt global aerosol products in SST analysis system**
**Deliverable: Benchmarking of improvements in NOAA decision support **
**Research-to-operation transition**
**Optimize the configuration to fit operational resource and time constraints**
**Manage the logistics for operational implementation**
**Deliverable: Operation implementation**

**An end-to-end work plan**

**In Progress**

## Aerosol products from EC GEMS (Global and regional Earth-system Monitoring using Satellite and in situ data)

| Products | Usage |
| --- | --- |
| 4D distribution of aerosol concentrations (troposphere and stratosphere) | climate research; monitoring of the atmospheric chemical composition; monitoring of the stratosphere (air traffic); monitoring of volcanic eruptions for local populations; initial and boundary conditions for regional air quality models |
| 4D distribution of aerosol optical properties (troposphere and stratosphere) | atmospheric corrections for remote sensing of land surfaces and ocean;
prediction of surface UV radiation |
| Surface distribution of particulate matter PM | regional air quality |
| Improved visibility range | air traffic, tourism |
| Improved photosynthetically active radiation (PAR) at the surface | study of the carbon cycle; monitoring of the Kyoto protocol |
| Aerosol deposition flux (dry and wet) | study of the ocean biology; impact on ecosystems (acid rain monitoring) |
| Improved photolysis rates | regional air quality; global monitoring of the atmospheric chemical composition |
| Improved surface, atmospheric, and top-of-atmosphere radiative budget | climate research |

**Aerosol products from EC GEMS (**_**G**_**lobal and regional **_**E**_**arth-system **_**M**_**onitoring using **_**S**_**atellite and in situ data)**

## Thank You