CO2 at WLEF in a Global Context

1
CO2 at WLEF in a Global Context
Adam Wolf, Brent Helliker and Joe Berry
2
Global Gas Exchange

• Need to have
• Information on Flow
• Concentration gradient
• Final
• Initial
• (acknowledgment to Scott Denning)

3
CO2 gradients across the atmospheric boundary
layer
Free troposphere
Altitude (m)
Atmospheric boundary layer
4
(No Transcript)
5
One-dimensional H2O and CO2 Budgets
(Flux difference estimate)
FNEE Fq(Ct - Cm)/(qt - qm)
6
Flux-Gradient
1.5
Eddy-Covariance
1.0
0.5
NEE mmol m-2 s-1
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
1997
1998
1999
2000
2001
From Helliker et al, 2004
7
Forward Modeling Atmospheric CO2 Processes
S. R. Kawa, G. J. Collatz (NASA Goddard Space
Flight Center) A. S. Denning (Colorado State
University) D. J. Erickson (Oak Ridge National
Laboratory and Duke University)
8
CO2 Concentration at WLEF simulations vs.
observations
9
(No Transcript)
10
(No Transcript)
11
Fung, IY, Tucker, CJ, KC Prentice, 1987 JGR
12
(No Transcript)
13
CO2 Balance of the polar region (75-90N)
14
(No Transcript)
15
(No Transcript)
16
Some conclusions

• The one-dimensional budgeting approach appears to
  miss flux and introduce a delay.
• Northward transport and mixing in the polar cell
  appears to be the cause.
• This transport appears to be linked with
  transport of heat from the sub-tropics to the
  pole.
• Little is know at this point about the reverse
  transport from the pole to the mid-latitudes.
• CO2 concentration at WLEF is impacted by both
  near- and far-field influences.
• We need to have an accurate global model to
  deconstruct these influences.