The Energy Budget of the Earths

1
Title slide

• The Energy Budget of the Earths
• Climate System
• Bing Lin
• NASA Langley Research Center, Hampton, VA, USA
• The Annual Meeting of
• the NASA Energy and Water-cycle Studies (NEWS)
• Huntsville, Alabama
• September 19-21, 2007

2
Outline

• Introduction EC for climate studies
• Current targeted areas of NEWS
• Energy balance of the atmosphere
• Uncertainties in current sat. data sets
• Land surface fluxes
• Global annual means
• Surface heat distributions
• Decadal variations
• Summary

3
Introduction

• Energy balance one of the fundamental physical
  processes of the climate system.
• Entwined relationship between the energy and
  water cycles.
• Horizontal and vertical heat transports.
• Studies reanalyses potentially large errors,
  mass corrections needed
• results heat transports, global/large scale
  balances, interannual variability.

4
Introduction (cont.)

• Satellite radiative energy, sea surface
  turbulent heat fluxes.
• Ocean heat storage changes, decadal variations of
  global heat budgets.
• Poleward heat transports from TOA radiation
  estimations.

2.5
1.5
Heat storage (W/m2)
0.0
Wong et al. JC, 2006
-1.0
Time (year)
1992
2004
5
Introduction (cont.)
6
Zhang et al. JGR, 2007
0
Heat transport (pW)
-6
90?
-90?
0?
Latitude
meridional heat transports from TOA radiation
6
Key areas

• Ocean and Land surface turbulent fluxes
• sensible latent heat moisture
• Radiative energy - TOA surface
• direct measure calculated
• Horizontal heat and moisture transports
• Vertical profiles
• atmospheric states heating rates
• Energy and moisture consistencies

7
Introduction (cont.)

• Blended data satellite radiation, in-situ
  assimilation turbulent fluxes 20 W/m2
  systematic errors insufficient SW
  absorption!

Yu et al., JGR, 1999
8
Some critical issues

• Annual budgets SW absorption, poleward heat
  transports (atmo./ocean components)
• Diurnal, seasonal, interannual, and decadal
  variations
• Energy and moisture budgets within key physical
  processes convection, precipitation, vegetation
• Integrated (multi-sensor/multi-spectral)
  satellite retrievals
• Some processes snowfall, snow melting, ice
  sheets, frozen soil, etc.

9
NEWS EC Projects TOA and SFC

• Sea surface flux
• Judy Curry, Carol Anne Clayson et al.
• Land surface flux
• Matthew Rodell et al., Alan Betts
• Precipitation
• Robert Adler et al.
• Water cycle
• Adam Schlosser et al.

10
Vertical heat distribution

• Radiative heating profile
• Tristan L'Ecuyer et al.
• Latent heat release profile
• Bill Olson et al.
• A-train radiation, clouds and aerosols Bruce
  Wielicki et al.
• A-train atmos. water and temp. profiles
• Eric Fetzer et al.

11
Horizontal heat transports

• Horizontal moisture transport
• boundary layer moisture wind velocity
• Tim Liu et al. (with scatterometer)
• Frank Wentz et al.
• Calculated heat transports
• Energy Cycle integrated data

12
regional observations data analysis

• Validation and surface sites
• Dong and Mcfarlane
• Field experiments
• Satellite moisture storage and validation
• Analysis predictions data/model results

13
Critical non-NEWS data

• Radiation data
• ERBE/CERES, ISCCP, SRB
• Sea surface fluxes
• GSSTF, HOAPS
• 4-D Data assimilation (quasi-data)
• Goddard assimilation system
• NCEP, ECMWF

14
Atmospheric heat budget

• Radiation
• TOA sfc - SRB, CERES, ISCCP-FD
• bias errors 10 W/m2
• Sea surface turbulent fluxes
• GSSTF, HOAPS
• bias errors 7 W/m2
• Precipitation GPCP
• atmospheric latent heat balance
• annual mean errors 5

15
Atmospheric heat budget

• Land surface fluxes GLDAS/MOSAIC
• heat storage, Bowen ratio, SRB
• Rnet LH SH S (1)
• B LH/(LHSH) (2)
• negligible horizontal heat transport
• forced in energy balance
• in daily monthly time scale

16
Sfc Net Radiation
17
Atmos. Net Radiation
18
sfc turbulent fluxes
latent heat
sensible heat
19
sfc total heat budget
20
annual mean heat balance
latitude
latitude
latitude
21
oceanic heat transport
6
3
Ocean heat transport (pW)
0
-3
-6
-90?
0?
-60?
60?
-30?
30?
90?
latitude
Zhang et al., JGR, 2007
22
decadal variations (TOA)
LW 0.7 W/m2 SW -2.1 W/m2 net 1.4 W/m2
These radiative changes may be related to the
changes in ocean heat storage. Decadal partly
contributed to decadal latent heat.
Wong et al. JC, 2006
23
another potential change water
bigger than radiation obs.
Wentz at al., Science 2007
24
decadal variations radiation
2.4 change ?Rsfc 2.1 2.7 W/m2
Time (year)
black globe red ocean green land
25
decadal variations total
Atmos. Total
LH
Time (year)
some indication of latent heat change
black globe red ocean green land
26
decadal variations precip.
No clear change in GPCP precipitation data How
to reconcile the differences among radiation,
latent heat, and precipitation data sets?
GPCP
Time (year)
black globe red ocean green land
27
Summary

• NEWS has considerable investments on important
  components of atmospheric EC, especially on sea
  surface and vertical and horizontal heat
  transports.
• Many data sets not under NEWS are also critical
  for EC analysis.
• The errors in annual atmospheric energy balance
  are less than half found about 8 years ago, and
  are within systematic error ranges of sfc
  radiative and turbulent fluxes. Progresses in
  satellite observations of sfc radiation and sea
  surface turbulent fluxes significantly reduce the
  observational errors.

28
Summary (conti.)

• Although it has significant coverage on EC, NEWS
  still has some gaps, especially on land surface
  and cold region processes.
• Although there is no significant evidence on the
  insufficient SW absorption, the systematic errors
  in annual mean atmospheric budgets are no small.
  More work on sfc radiation and turbulent fluxes
  are needed.
• Due to large uncertainties in both decadal sfc
  radiation and precipitation data sets, there are
  considerable differences among energy data sets.