# Presentation: 254496

## AURA VALIDATION DURING THE ARCTAS AIRCRAFT MISSION

**ARCTAS**

** ****Two 3-week deployments: April 2008 (Fairbanks/Thule), July 2008 (Edmonton)**
** ****Three NASA aircraft: DC-8 (in situ chemistry and aerosols), P-3B (radiation and in situ aerosols), B-200 (aerosol remote sensing and CALIPSO validation)**

**Daniel J. Jacob, Harvard University**

**Aircraft missions of the NASA Tropospheric Chemistry Program**

## URGENT NEED TO BETTER UNDERSTANDARCTIC ATMOSPHERIC COMPOSITION AND CLIMATE

**ARCTIC IS A BEACON OF GLOBAL  CHANGE**
**Rapid warming over past decades**
**Receptor of mid-latitudes pollution – arctic haze, **
**     ****ozone build-up, accumulation of persistent pollutants**
**Large and increasing influence from boreal forest fires in Siberia and North America**
**POTENTIALLY LARGE RESPONSE**
**Melting of polar ice sheets and permafrost**
**Decrease of snow albedo from soot depostion**
**Efficient UV/Vis absorption by ozone, soot**
**Halogen radical chemistry**
**UNIQUE OPPORTUNITY FOR NASA**
**Large NASA satellite fleet for atmospheric composition and radiation **
**Interagency and international collaboration through POLARCAT international atmospheric chemistry field program during IPY**
**Broader synergies enabled by other IPY activities (OASIS for oceans, etc.)**

## ARCTAS STRATEGY: use aircraft to increase value of satellite data for models of arctic atmospheric composition and climate

**  ****Satellite instruments: CALIPSO, **
**  ****OMI, TES, HIRDLS, MLS, **
**  ****MODIS, AIRS, MISR, MOPITT**

** ****Aerosol optical depth, properties**
** ****CO, ozone, BrO, NO****2****, HCHO**

**Aircraft: DC-8, P-3B, B200**

** ****Detailed in situ chemical **
**and aerosol measurements**
** ****Remote sensing of ozone, aerosol, surface properties**

**Models: CTMs, GCMs, ESMs**

** ****Source-receptor relationships for Arctic pollution**
** ****Effects of boreal forest fires**
** ****Aerosol radiative forcing**
** ****Arctic chemistry**

**Data assimilation**
**Diagnostic studies**

** ****Retrieval development & validation**
** ****Observational error characterization**
** ****Correlative information**
** ****Local chemical & aerosol processes**

**ARCTAS STRATEGY: use aircraft to increase value of satellite data for models of arctic atmospheric composition and climate**

## ARCTAS Science Theme 1:Transport of mid-latitudes pollution to the Arctic

**ARCTAS Science Theme 1:****Transport of mid-latitudes pollution to the Arctic**

** ****What are the transport pathways **
**for different pollutants?**
** ****What are the contributions from   different source regions, what are the source-receptor relationships?**

**Satellite capabilities:**** **
** ****CO (TES, AIRS, MOPITT)**
** ****Ozone (TES, OMI-MLS)**
** ****aerosols (CALIPSO, MODIS, MISR)**
**Aircraft added value:**** **
** ****detailed chemical composition**
** ****tracers of sources **
** ****vertical information**

***J. Worden, JPL***

**European influence        Seasonal sulfate build-up    TES 600 hPa CO, March 2006**

**TOPSE**

***Scheuer et al., 2003***

**Feb**

**May**

## ARCTAS Science Theme 2: Boreal forest fires

**ARCTAS Science Theme 2: Boreal forest fires**

**Fire trend over past decade       CALIPSO view of fire plume  MISR injection height **

**Siberian fire,**
**July 26, 2006**

***A. Soja, LaRC                                           C. Trepte, LaRC                              R. Kahn, JPL***

** ****What is the chemical composition &**
**evolution of the fire plumes?**
** ****What are their aerosol optical properties, how do these evolve?**
** ****What are the injection heights, what are the implications for transport & chemistry?**

**Satellite capabilities:**** **
** ****aerosols  (CALIPSO, MODIS, MISR, OMI)**
** ****CO (TES, AIRS, MOPITT, MLS)**
** ****Ozone (TES, OMI-MLS)**
**Aircraft added value:**** **
** ****detailed chemical composition**
** ****aerosol properties **
** ****pyroconvective outflow**

## ARCTIC Science Theme 3: Aerosol radiative forcing

**ARCTIC Science Theme 3: Aerosol radiative forcing**

**        ****CALIPSO clouds and smoke                 Arctic haze     MISR true-color fire plume**

***C. Trepte, LaRC                                                                                  R. Kahn, JPL***

** ****What is the regional radiative forcing from Arctic haze, fire plumes?**
** ****How does this forcing evolve during plume aging?**
** ****What are the major sources of soot to the Arctic?**
** ****What is the effect of deposited soot on ice albedo?**

**Satellite capabilities:**** **
** ****UV/Vis/IR reflectances (Cloudsat, **
**  ****MODIS, MISR, OMI)**
** ****multi-angle sensing (MISR)**
** ****lidar (CALIPSO) **
**Aircraft added value:**** **
** ****detailed in situ aerosol characterization**
** ****remote sensing of radiances, fluxes**
** ****BRDF of surface **

## ARCTAS Science Theme 4: Chemical processes

** ****What is the HO****x****/NO****x**** chemistry in the Arctic?**
** ****What drives halogen radical chemistry in the Arctic, what is its regional extent?**
** ****What are the regional implications of halogen chemistry for ozone and mercury?**
** ****How does stratosphere-troposphere exchange affect tropospheric ozone in the Arctic?**

**Satellite capabilities:**** **
** ****Ozone (TES, OMI/MLS)**
** ****BrO (OMI)**
** ****strat-trop exchange (HIRDLS)**
** ****CO (TES, AIRS, MOPITT)**
**Aircraft added value:**** **
** ****detailed chemical characterization, constraints on photochemical models**
** ****validation of OMI tropospheric BrO**
** ****HO****x**** measurement intercomparison**

## AIRCRAFT PLATFORMS, PAYLOADS

**DC-8: in situ chemistry and aerosols**
**Ceiling 37 kft, range 4000 nmi, endurance 9 h**
**Payload: O****3****, H****2****O, CO, CO****2****, CH****4****,  NO****x ****and HO****x**** chemistry, BrO, mercury, NMVOCs, halocarbons,  SO****2****. HCN/CH****3****CN, actinic fluxes, aerosol composition, aerosol mass and number concentrations, aerosol physical and optical properties, remote ozone and aerosol**

**B-200: aerosol remote sensing and CALIPSO validation**
**Ceiling 32 kft, range 800 nmi, endurance 3.5 h**
**Payload: High Spectral Resolution Lidar (HSRL)**
**                ****Research Scanning Polarimeter (RSP)**

**P-3B: radiation and in situ aerosols**
**Ceiling 30 kft, range 3800 nmi, endurance 8 h**
**Payload: optical depth, radiative flux, radiance spectra, aerosol composition, black carbon**

## ARCTAS BASES AND NOMINAL DC-8/P-3 RANGES

**Fairbanks**
**Thule (suitcase)**
**Summer:**
**Edmonton**

**ARCTAS BASES AND NOMINAL DC-8/P-3 RANGES**

## HOW CAN ARCTAS BEST SERVE AURA VALIDATION NEEDS IN THE ARCTIC IN THE CONTEXT OF ARCTAS SCIENTIFIC GOALS?

**April deployment:**
**Identified priority: OMI BrO validation**
**What other useful tropospheric information can we expect from Aura in April over the Arctic? Ozone columns? Ozone structure at tropopause? CO pollution plumes?**
**What environments/surfaces provide the best/worst opportunities for satellite observation? Which are most important for validation? **
**Is there a big seasonal transition in Aura viewing capabilities over the course of April? Is late April much better than early April?**
**Can ARCTAS enable not just the validation but also the development of retrieval algorithms?**
**July deployment:**
**Identified priority: Ozone-CO-NO****2****-HCHO-aerosols validation in forest fire plumes**
**Also TES methane (Greg Osterman presentation)**
**Are there other validation needs beyond what has been done before?  Are there important new environments/conditions to validate? Does concern over instrument drift justify a repeat of past validation?**