Hello Committee, Meet Me!

Quick and Dirty Biography (1)

Born: July 12, 1975, Atlantic City, NJ

Lived in Brigantine, NJ and Linwood, NJ; have one sister

Mainland Regional High School (1989-1993) founded underground newspapers graduated 3rd in class of 251

Oberlin College 1993-1997, B.A. Oberlin, Ohio Majors: Environment Studies & Computer Science published travel guidebook for Oberlin Advisor: Bruce Simonson, Geosciences

Quick and Dirty Biography (2)

Jobs and Activities from 1989-1999

Sub maker and waiter – Northfield, NJobtained private pilot license – Elyria, OHMedical software tester – Horsham, PATeacher’s aide, 1st and 2nd grade, Oberlin Public SchoolsAssistant ScoutmasterMembership secretary to Oberlin Student Cooperative AssociationOrganic farm apprentice, Palermo, MaineU.S. Forest Service seasonal naturalist, Carson City, NVEnvironmental Protection Agency intern to Office of Pesticides, Arlington, VA; Seattle, WA; Jakarta, Indonesia

Quick and Dirty Biography (3)University of Minnesota 1998-2000 – Geography, M.A.

Funding: MacArthur Foundation fellowship for the Interdisciplinary Study of Global Change / U. Minn Cart. Lab

Advisor: Horward Veregin

Worked with Ken Davis in 1998-2000 on Southern Great Plains 1997 experiment

M.A. “Plan B” paper titles:Surface energy flux dependence on remotely-sensed soil moisture and vegetation in the Southern Great Plains experiment

Point-source air pollution risk buffers from long-term climate data and Gaussian plume models

Interaction of resolution and classification in high-resolution urban/suburban land cover imagery

Quick and Dirty Biography (4)

Desai, A., K. Davis, C. Senff, S. Ismail, E. Browell, 2003, Surface energy flux distribution and convective boundary layer development in the Southern Great Plains 1997 experiment, submitted to Journal of Hydrometeorology

Davis, K, C. Senff, A. Desai, R. Dobosy, D. Lenschow, S. Ismail, E. Browell, Evaluation of the boundary layer water vapor budget using airborne DIAL and in situ measurements, in preparation

several conference papers and posters, modeling work with Brian Reen and Dave Stauffer

Got married in June 2000

12 July (1200 CST)

13 July (1200 CST)

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40 49 58 67 76 85Easting (km)

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500 2000meters above ground level

Quick and Dirty Biography (5)

Started working on old-growth flux tower in Sept. 2000 as research fellow for Eileen Carey at UMN:

DOE TCP Project

PIs: Eileen Carey, Ken Davis, Paul Bolstad, Margaret Davis

“Quantifying carbon sequestration potential of mid and late-successional forests in the upper Midwest”

purchased, built, installed and calibrated flux, micromet and ecophysiology station, operating since August 2001

Quick and Dirty Biography (6)

Started Penn State PhD program in spring of 2002

Advisor: Ken Davis

took M.S. core, Turbulence,Bioclimatology, seminars

completed Earth system requirement with Global Carbon Cycle, spring 2002

participated in IHOP field experiment in May 2002passed Technical English Competency Exam in summer of 2002passed Candidacy exam in January of 2003completed 3 credit seminar requirementchair of Graduate Advisory Committee

Gist of my research proposalOver the last two decades, researchers have established a network of

long-term CO2 flux measurements that apply the eddy-covariance technique. This network of terrestrial flux sites has improved our estimates of net ecosystem exchange (NEE). Despite the growing number of NEE measurement sites around the world, few are located in old-growth forests.

I propose to compare the ecosystem and regional scale carbon cycle processes at an old-growth site to a flux site located in a nearby second-growth forest using a number of techniques including remote-sensing.

Why? Because we don’t know for sure what will happen to carbon exchange with forest age

What is NEE?

-1 * NEE = NEP = Net Primary Production (NPP) - Heterotrophic Respiration (RH)

NPP = Gross Primary Production (GPP or GEP or Photosynthesis) – Autotrophic Respiration

Hypotheses (1)1.) Net ecosystem uptake of carbon in an upper-Midwest undisturbed old-growth forest is smaller than a nearby second-growth forest, but it still a net carbon sink. This decrease is NEE is due to an linear increase with ecosystem respiration with stand age due to increased biomass and coarse woody debris and a leveling off of ecosystem net photosynthesis with stand age. Quantification of this hypothesis will allow for a rough approximation of the maximum potential for carbon storage of forests in the upper Midwest that follow a similar successional pathway.

Hypotheses (2)1.) Net ecosystem uptake of carbon in an upper-Midwest undisturbed old-growth forest is smaller than a nearby second-growth forest, but it still a net carbon sink. This decrease is NEE is due to an linear increase with ecosystem respiration with stand age due to increased biomass and coarse woody debris and a leveling off of ecosystem net photosynthesis with stand age. Quantification of this hypothesis will allow for a rough approximation of the maximum potential for carbon storage of forests in the upper Midwest that follow a similar successional pathway.

2.) Both forest ecosystems have similar sensitivities in forest carbon uptake to climate variability. Verification of this claim will help explain regional scale interannual variability in carbon fluxes.

Hypotheses (3)1.) Net ecosystem uptake of carbon in an upper-Midwest undisturbed old-growth forest is smaller than a nearby second-growth forest, but it still a net carbon sink. This decrease is NEE is due to an linear increase with ecosystem respiration with stand age due to increased biomass and coarse woody debris and a leveling off of ecosystem net photosynthesis with stand age. Quantification of this hypothesis will allow for a rough approximation of the maximum potential for carbon storage of forests in the upper Midwest that follow a similar successional pathway.

2.) Both forest ecosystems have similar sensitivities in forest carbon uptake to climate variability. Verification of this claim will help explain regional scale interannual variability in carbon fluxes.

3.) Ecosystem scale CO2 flux depends directly on leaf and soil level component carbon and water fluxes, which change as forests age (i.e. stem respiration decreases, leaf light use efficiency decreases, coarse woody debris respiration increases with stand age). Testing this hypothesis will help determine how the physical processes behind carbon uptake change with stand age.

Hypotheses (4)4.) Regional scale CO2 flux is a mosaic of ecosystem scale CO2 fluxes. Also, the regional scale flux can be modeled with process-based models driven by climatology and remote sensing. If so, then we could directly upscale from ecosystem to regional scale.

Hypotheses (5)4.) Regional scale CO2 flux is a mosaic of ecosystem scale CO2 fluxes. Also, the regional scale flux can be modeled with process-based models driven by climatology and remote sensing. If so, then we could directly upscale from ecosystem to regional scale.

5.) Other forests outside the region exhibit similar magnitudes of carbon uptake change with age. Also, we can create a general model of how this change will occur. Testing this hypothesis will help evaluate to what extent we can generalize the results found at our study site to other locations and thus possibly understand how forest carbon uptake might change at the continental or global scale.

Hypotheses - Relevance4.) Regional scale CO2 flux is a mosaic of ecosystem scale CO2 fluxes. Also, the regional scale flux can be modeled with process-based models driven by climatology and remote sensing. If so, then we could directly upscale from ecosystem to regional scale.

5.) Other forests outside the region exhibit similar magnitudes of carbon uptake change with age. Also, we can create a general model of how this change will occur. Testing this hypothesis will help evaluate to what extent we can generalize the results found at our study site to other locations and thus possibly understand how forest carbon uptake might change at the continental or global scale.

These hypotheses promulgate pieces to the puzzle of understanding how carbon storage in forest ecosystems generally change as they age. The results from testing these hypotheses will provide a way to estimate an upper-bound (barring disturbance) of the ability of terrestrial ecosystems to store carbon. This information is pertinent to formulating proper regional, national and international public policy for carbon emissions and sequestration.

Methods and Progress (1)

Sylvania Old-GrowthAge: 0-350, mean around 100Species: Hemlock-Maple-BirchLAI: 3.79 (hemlock), 4.06 (maple)Established: 8/2001

Willow CreekAge: 66 yrsSpecies: Maple-Basswood-AshCanopy height: 24.3 mLAI: 4.18Established: 5/1998

Climate: northern continentalmean temp around 4 degrees C80-90 cm precip/year100-300 cm snowfall/year

Methods and Progress (2)

Willow Creek Sylvania

Methods and Progress (3)

2002 Daily Total NEE

J F M A M J J A S O N D-8

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Sylvania -136 gC/m2/yr

Willow Creek -438 gC/m2/yr

2002 Cumulative NEE

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Sylvania NEE -136 gC/m2/yr

Willow Creek NEE -438 gC/m2/yr

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J F M A M J J A S O N D

Methods and Progress (4)

Nighttime Respiration vs Soil Temperature

10 12 14 16 18 205cm Soil Temperature (degrees C)

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ionm

ol C

O 2/m

2/s R(T) = 1e6 * kT/h *

exp( -(77.1 - (T * -0.08))/R*T

r2 = 0.96

R(T) = 1e6 * kT/h * exp( -(40.7 - (T * -0.21))/R*T

r2 = 0.702

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Willow Creek

Sylvania

PAR vs Photosynthesis

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Psyn = (( 26.0 * PAR ) / ( 549. + PAR )) - 1.18

r2= 0.99

Psyn = (( 33.3 * PAR ) / ( 480. + PAR )) - 2.11r2 = 0.99

Sylvania

Willow Creek

Methods and Progress (5)

2002 Daily Total Ecosystem Respiration

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ay Sylvania

806 gC/m2/yr

Willow Creek 646 gC/m2/yr

J F M A M J J A S O N D

2002 Daily Total Photosynthesis

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P g

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Sylvania 942 gC/m2/yr

Willow Creek 1083 gC/m2/yr

J F M A M J J A S O N D

Methods and Progress (6)

Methods and Progress (7)

2002 Sylvania Sapflow

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Hemlock

Sugar Maple

Yellow Birch

Methods and Progress (8)

Sylvania Old Growth Forest, WI, 2001MODIS GPP = 1503.49 gC m-2

Julian Day

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Biome-BGC output (left)Aerial photo (below)

Methods and Progress (9)

Is there any “atmospheric science” in this?

•Turbulence: eddy covariance, u* corrections, non-homogenous flow

•Micrometeorology: drainage flows (below canopy), advection, terrain issues, measurement of meteorological variables in forests, energy balance, hydrology (transpiration)

•Climatology: regional climate variability and change, response of ecosystems to climate (temp., radiation, precip., clouds)

•Trace gas chemistry: high precision CO2, regional flux through inversion

Earth systems science requires breadth in many disciplines: meteorology, biology, ecology, geology, chemistry, geography, …

PublicationsPosters:Ameriflux Science Meeting, Boulder, CO, October 22-23, 2002

The Carbon Balance of Forest Biomes, Society for Experimental Biology, Southampton, UK, April 1-4, 2003

North American Carbon Program PI meeting, Arlington, VA, May 12-14, 2003

Papers:A. Desai, E. Carey, B. Cook, K. Davis, in preparation, A year of

carbon storage at an old-growth hemlock-hardwood forest

Future papers:B. Cook, A. Desai, et al., Eyring model and soil respirationA. Desai, B. Cook, E. Carey, K. Davis, et al., Sylvania to Willow

Creek comparisonE. Carey, A. Desai, Component fluxes at SylvaniaE. Carey, A. Desai, Transpiration fluxes at Sylvania

Future PlansFunding:

Since 2002 – funded as research assistant by DOE (ends 12/03)(Renewal sent in March 2003)

Have applied for NASA Earth System Science fellowship

Plans:

Submit first Sylvania paper in early summer (July 2003)Complete regular fieldwork (June 2003, Oct 2003, Jan 2004)Comprehensive exam in August 2003Become a father in September 2003Work on comparison paper in fall of 2003Finish dissertation by spring 2005Defend by summer 2005Future jobs: congressional fellow, post-doc abroad, science

research institution

Thank you!