an earth system satellite mission? paul palmer, claire bulgin, and siegfried gonzi

An Earth system satellite mission?

Paul Palmer, Claire Bulgin, and Siegfried Gonzihttp://www.geos.ed.ac.uk/eochem

The Earth System

Mismatch between models and data

Talk outline

SolutionsExample science challengesConcluding remarks

Develop a framework of rapid response instruments?

Comprehensively monitor key atmospheric trace gases and particles?

Adopt integrated approach for measuring the Earth?

3 possible solutions

The velocity of climate change

Loarie et al, Nature, 2009

Ratio of temporal and spatial gradients of mean annual near-surface T = instantaneous local velocity necessary to maintain constant T

Some potential tipping points in the Earth system

Develop a framework of rapid response instruments?

Comprehensively monitor key atmospheric trace gases and particles?-- ESA ECVs-- EUMETSAT and NOAA activities

Adopt integrated approach for measuring the Earth?

3 possible solutions

Develop a framework of rapid response instruments?

Comprehensively monitor key atmospheric trace gases and particles?

Adopt integrated approach for measuring the Earth?

3 possible solutions

The NASA A-train is an example of the power of correlative measurements

But using correlative data properly is non-trivial…examples to follow

1. Source attribution of AODs

2. Quantifying pyroconvection injection heights

2 examples

Africa

We should think about systems as well as individual components

deposition

Primary and secondary aerosol sources: biomass

burning, biogenic, desert dust

Internally or externally mixed?

CCN

Fe fertilization

Ocean Ecosystem South America Africa

visibility

GlobAerosol AOD retrievals from

SEVIRI (0.6, 0.8, & 1.7m)

Prior information about aerosol type is required to infer AOD from observed

radiances using ORAC MAP

(SEVIRI = Spinning Enhanced Visible and Infrared Imager)

maritime (0), urban (1), continental (2), biomass burning (3), and desert dust (4).

GlobAerosol AOD retrieval uses brute-force approach

Time of day

Day

s

Additional information is available from SEVIRI and models

SEVIRI Dust IndexGEOS-Chem: Black carbon Sea salt

GlobalAerosol MAP scheme

Prior:Dust

Sea saltBiomass burning

Sulphate

Idea

l

AODs

GlobalAerosol MAP scheme:

DustSea salt

Biomass burningSulphate

Inte

rrim

AODdust

AODss

AODbb

AODso4

Additional information is available from SEVIRI and models

Saharan Dust Index remove dust contamination in nighttime SSTretrievals.

PCA of brightness temperatures (3.9—8.7m, 2.9—12m, and 11—12m).

GEOS-Chem Chemistry Transport Model 3-D black carbon aerosol and sea salt distributions

BC evaluated via CO and TES

Bulgin et al, 2010Cloudy scenes identified by EUMETSAT cloudmask

Bulgin et al, 2010

Bulgin et al, 2010

Bulgin et al, 2010Large AOD differences has implications for

quantifying climate effects

Bulgin et al, 2010Future challenge will be to incorporate coexisting

aerosol classes

Estimates of global emissions from biomass burning

Biomass burning (Tg Element/yr)

All Sources (Tg Element/yr)

Biomass burning (%)

CO2 3500 8700 40

O3* 420 1100 38

CO 350 1100 32NMHC 24 100 24NOx 8.5 40 21

CH4 38 380 10

EC 19 22 86

WHERE AND WHEN? Polar-orbiting satellites have sufficient coverage to infer information about variability on timescales from diurnal to year-to-year

5-years of Terra MODIS data (11/00 – 10/05)

HOW BIG? Bottom-up emission estimates

M = A x B x a x b

Grams of dry matter burned per year

Total land area burned annually

The average organic matter per unit area

Fraction of above ground biomass relative average biomass B

Burning efficiency of the above ground biomass

Emission factors for flaming and smouldering fires

Forward model H

Inverse model

Observations yEmissions x

BB

BF

Top-down methodology

)]([ aobs

ap H xyKxx

Posterior Prior Gain matrix Observations Forward model

ap PKHP )( 1

)( aobs H xy

Top-down emission estimates based on inverse model calculations or process-based models

GFEDv2 CO Emissions for JJASO 2006 [g CO/m2]

Injection height Smoke entrained in

mean flow

Injection height is a complex function of fuel loading, overlying meteorology, etc

Transport of emissions depends on the injection height

NASA Multi-angle Imaging SpectroRadiometer- MISR

In orbit aboard Terra since December 1999

Stereographic projection provides information about fire smoke aerosol height layer

9 view angles at Earth surface: nadir to 70.5º forward and backward (446, 558, 672, 866 nm)

275 m - 1.1 km sampling

Val Martin et al, 2010

We use CO as a tracer for incomplete combustion

We use cloud-free data from two instruments aboard the NASA Aura spacecraft (left):

Tropospheric Emission Spectrometer (TES)

Microwave Limb Sounder (MLS)

Over burning scenes, together they are sensitive to changes in CO from the lower troposphere to the upper troposphere/lower stratosphere

i

i

im

y

e

m

e

y

We develop the traditional surface emission inverse problem

Both sides describe the sensitivity of the measured quantity y to changes in surface emissions e

We estimate emitted CO mass in five regions from 0 – 15 km.

During June-October 2006 we use 1785 TES profiles (672 colocated with MLS)

Omitting gory details, only 2-3% of retrievals failed.

Define an injection height as the maximum height at which:

1)Posterior uncertainty is smaller than prior by 50%

2)Posterior mass is higher than the prior mass

33% pass this criterion; remaining 67% assume boundary layer injection

•We estimate an injection height of greater than 10 km (recall we estimate mass over large vertical regions)

•Posterior CO mass increased by 50% due to biomass burning.

(Limited) evaluation of our product: Indonesia, October 2006

2 = cloud 3 = aerosol

Level of neutral buoyancy = 138 hPa

Nearby radiosonde

Disproportionate impact of large fires: Cctrl-Cptb

Longitude [deg]

Boreal (42-67oN)Tropics (0-30oS)Pr

essu

re [h

Pa]

Concluding remarksAtmosphere and land/ice/ocean missions are often on different platforms.

Planned ESA/NASA missions are driven by engineering rather than science

Now links realized between Earth components should we be designing Earth system missions?

Eg OCO-2: CO2 OCO-3: CO2/CH4/CO/leaf phenology?