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DOWN AND DIRTY: USING A CONTINENTAL, NOT-SO-TALL TOWER TO STUDY TRENDS... Description: Precise CO2 concentration
measurements at marine stations and tall towers are crucial for quantifying
global trends in atmospheric CO2 concentrations.
We propose that measurements in the continental planetary boundary layer—the
poor cousin of the clean background stations—can be used to understand trends
in, and controls, of atmospheric CO2 concentrations
at local and regional scales as well as global scales. The key is choosing
appropriate time scales of integration for the data. In the US Southern Great
Plains, we are measuring precise CO2 concentrations
continuously at 2–60 m and weekly at 300 and 3300 m above ground level (agl). CO2 flux is measured in individual crop fields and pastures (4 m
towers) and at 60 m. The precise CO2 concentrations
show strong continental influence in both diurnal and seasonal cycles. In
continental regions, atmospheric CO2 profiles are
strongly influenced by atmospheric dynamics as well as ecosystem and
anthropogenic fluxes. Relating site level measurements or atmospheric profiles
to regional CO2 budgets requires methods to represent or evaluate these
influences. We observe inter-annual differences in the
climatology of diurnal cycles (seasonal average diurnal cycles). Using the several years’ data for
boundary layer concentrations, the annual trend in CO2
growth nearly matches the value estimated by National Oceanic and
Atmospheric administration (NOAA) Climate Monitoring Diagnostic
Laboratory for our latitude band. Author's Names: M.S. Torn, M.L. Fischer, S.C. Biraud, W.J. Riley, et al Added on: 25-Jul-2005 Downloads: 39 Home Page | Comment on Proceeding | Details Category: Abstracts/Land Use and the Terrestrial Carbon Cycle
INFLUENCE OF THE CO2 LATITUDINAL GRADIENT ON THE OBSERVATIONS AT THE MEDITERRANEAN ... Description:
Measurements of CO2
concentration are carried out on a weekly basis since 1992 on the island of Lampedusa
(35.5°N, 12.6°E), in the Mediterranean.
Measurements are based at the Station for Climate Observations, which rests on
a rocky plateau (45 m asl) on the North-Eastern coast of the island, and are
made with a NDIR analyzer. World Meteorological Organization (WMO) reference standards are used for
calibrations. Continuous measurements
were started in 1998; they were interrupted in early 2003, and activated again
in 2005. The continuous observations show evidence of a small daily cycle
(amplitude < ±1 ppm) only during the months of June, July, and August. Mean
annual cycles derived from weekly flask measurements show a dependency on the
wind origin: the annual cycle and the annual CO2 mean are smaller
for winds originating from the Southern sectors, than for winds from Northern
sectors. The continuous measurements were combined with daily backward airmass
trajectories to identify the dependency of the CO2 amount on the
airmass origin. Trajectories provided by National Oceanic and Atmospheric
administration / Air Resources Laboratory (Hysplit) are used. During winter,
low CO2 is generally connected to Southern/South-Eastern airmasses.
In summer airmasses from North often display lower CO2 content, due
to the influence of the European sink.
Author's Names: A. di Sarra, P. Chamard, S. Piacentino, et al Added on: 28-Jul-2005 Downloads: 46 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
ANTHROPOGENIC CARBON DIOXIDE EMISSIONS AT THE STATE AND MONTHLY LEVELS Description: CO2 emissions
from fossil-fuel combustion can be estimated at the state or monthly level even
when full data on fuel combustion are not available. Our hypothesis is that a
representative proxy can accurately estimate the pattern of CO2
emissions if a sufficient fraction of the total can be represented, even if the
dataset used does not cover all energy consumption sectors. Our
approach employs monthly sales data for each state from the U.S. Department of
Energy’s Energy Information administration (EIA). This is used to estimate the
relative proportions of solid, liquid and gaseous fossil fuels for each state
for each month. Author's Names: J. Gregg, L. Losey, R. Andres, G. Marland Added on: 29-Jul-2005 Downloads: 45 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
PERFORMANCE ANALYSIS OF THE LOFLO CONTINUOUS CO2 ANALYSER: MONITORING OF BASELINE AND ... Description: Results are presented
from recent evaluations of multiple “LoFlo” CO2 analysers. These
experiments were conducted at both an urban site (Aspendale, a suburb of Melbourne, Australia),
and the Cape Grim baseline site. Figure 1 shows the
preliminary results from an overlap experiment involving two LoFlo analysers (identified
here as LoFlo-2A, and LoFlo-2B, each one operating with its own suite of
calibration gases) measuring marine boundary layer air from a shared single air
intake at the Cape Grim Baseline Air Pollution Station, in northwest Tasmania,
during April/May 2005. The figure shows the differences between hourly CO2
values from the two analysers, during those periods when baseline conditions
were experienced. The seven high pressure, CO2-in-dry air
calibration standards used for the LoFlo-2B system have been calibrated at the Carbon
Cycle Gases Group (CCGG), United States National Oceanic and Atmospheric
administration (NOAA), Climate Monitoring and Diagnostics Laboratory (CMDL),
designated by the World Meteorological Organization (WMO) as the CO2
Central Calibration Laboratory.
Author's Names: M.V. van der Schoot, L.P. Steele, R.J. Francey, et al Added on: 08-Aug-2005 Downloads: 49 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
The Global Effort to Understand Carbon Dioxide Description: Opening Remarks by:
James R. Mahoney, Ph.D.
Assistant Secretary of Commerce for Oceans and Atmosphere
NOAA Deputy administrator
Director: US Climate Change Science Program
September 26, 2005 Author's Names: Dr. James R. Mahoney Added on: 25-Sep-2005 Downloads: 90 Home Page | Comment on Proceeding | Details Category: Speaker Presentations
THE NOAA CMDL TALL TOWER OBSERVING NETWORK: NEW RESULTS AND PLANNED EXPANSION Description: The
National Oceanic and Atmospheric administration’s Climate Monitoring and
Diagnostics Laboratory has been working to build a network of tall tower
monitoring sites over the US
since the early 1990’s. Tall tower CO2 mixing ratio measurements are
sensitive to upwind fluxes over scales of hundreds of kilometers. Such
measurements therefore place strong constraints on estimates of regional scale
carbon budgets. We have used the Stochastic Time Inverted Lagrangian Transport
(STILT) model to evaluate the relative contributions of upwind sources and
sinks to simulated CO2 mixing ratios at existing and proposed new
tower sites. For example, sampling footprints from STILT have been combined
with estimates of hourly ecosystem CO2 fluxes from the Simple
Biosphere (SiB) model to investigate the spatiotemporal influence of different
biomes on observed CO2 concentrations at the towers. Contributions
of fossil fuel and oceanic CO2 fluxes can also be quantified using
this method.
Author's Names: A.E. Andrews, P.S. Bakwin, P.P. Tans, J. Kofler, C. Zhao, J. Added on: 25-Jul-2005 Downloads: 51 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
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