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| MINERAL CARBON DIOXIDE SEQUESTRATION: STILL A VIABLE OPTION Description:
This
paper provides background and summarizes evidence supporting the possibility of
developing a low-cost mineral carbon dioxide sequestration technology.
Filesize: 19.09 Kb Added on: 01-Aug-2005 Downloads: 294 Home Page | Comment on Proceeding | Details Category: Abstracts/Managing the Carbon Cycle
LONG-TERM CONSEQUENCES OF CONTINUED CARBON DIOXIDE EMISSION TO THE ATMOSPHERE Description: Continued emissions of carbon dioxide to the
atmosphere will affect climate and ocean chemistry. These consequences can be
anticipated by consideration of basic physical principles, past climates, and
calculations. Emission of 5,000 PgC (= amount of carbon in conventional fossil-fuel
resources) over a few centuries could produce radiative forcing of climate of
about 10 W m-2 which could be expected to produce global mean
warming of ~4 to 12 °C. Warming in this
range would have large biological and human consequences. It could threaten the
ice sheets and lead to a long-term sea-level rise of 70 m. Ocean pH could decrease by 0.7 units, making
the oceans more corrosive to carbonate minerals than they have been for many
millions of years. From the perspective of geology and biological evolution,
these changes would occur rapidly, overwhelming most natural processes that
would buffer CO2 changes occurring
over longer time intervals, and thus may produce changes at a rate and of a
magnitude that exceed the adaptive capacity of at least some biological
systems. To find comparable events in Earth history, we need to look back tens
of millions of years to rare catastrophic events. Filesize: 21.50 Kb Added on: 27-Jul-2005 Downloads: 274 Home Page | Comment on Proceeding | Details | Comments (1) Category: Opening Talks
IMPACT OF CLIMATE-CARBON CYCLE FEEDBACKS ON EMISSIONS SCENARIOS TO ACHIEVE STABILISATION Description: At present, approximately half of anthropogenic CO2
emissions are absorbed by the land and oceans [Jones and Cox, 2005], but climate changes may act to reduce this
uptake, leading to higher CO2 levels for a given emission scenario [Cox et al., 2000, Friedlingstein et al., 2005, in prep.]. Less attention has been
paid to the potential impact of carbon cycle feedbacks on the emissions
reductions required to achieve stabilisation (the so called “permissible
emissions”), although this is arguably more pertinent to the issue of avoiding
dangerous climate change in the context of the United Nations Framework
Convention on Climate change. Filesize: 103.88 Kb Added on: 29-Jul-2005 Downloads: 210 Home Page | Comment on Proceeding | Details Category: Abstracts/Managing the Carbon Cycle
GREENHOUSE GAS CO2, CH4 AND CLIMATE EVOLUTION SINCE 650KYRS DEDUCED FROM ANTARCTIC ICE CORES Description: Ice cores are unique archives of past climatic and atmospheric
conditions through the isotopic composition of the ice and the analysis of the
air bubbles trapped. In 1999 Petit et al published the reconstruction of the
Antarctic climate and atmospheric composition over the last 420 000 years from
the Vostok ice core. This record covered the last four glacial inter glacial
cycles back to the end of the marine interstadial 11 (MIS 11). It has revealed
the close relationship between the atmospheric part of the carbon cycle and the
climate. With CO2 concentration oscillating between 180 and 280 ppmv
during the last 4 climatic cycles. In
a similar way the methane concentration followed closely
temperature on glacial interglacial time scales, with millennial-scale
structures during glacial times which appear out of phased with Antarctic
temperature but, at least for the last glaciation, in phase with the Greenland rapid climatic oscillations, as revealed by the
GISP and GRIP ice cores. Filesize: 15.87 Kb Added on: 27-Jul-2005 Downloads: 199 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
SUBSTRATE INDUCED GROWTH RESPONSE OF SOIL AND RHIZOSPHERE MICROBIAL COMMUNITIES UNDER ELEVATED CO2 Description: The
maximal specific growth rate of microorganisms from rhizospheres of Populus deltoides grown under normal CO2 concentration
in the atmosphere (400 ppm) was lower compared to the assessments made for
plots under elevated CO2 (800 and 1200 ppm). A similar conclusion
was made for microbial communities from soil under winter wheat and sugar beets
grown under 370 and 550 ppm CO2 in the atmosphere. Three to four
years fumigation of field plots with elevated CO2 has been shown to
result in the formation of rhizosphere microbial communities characterized by
faster specific growth rates as compared to microbial community under control
plants. Filesize: 147.23 Kb Added on: 26-Jul-2005 Downloads: 195 Home Page | Comment on Proceeding | Details Category: Abstracts/Impacts of High CO2 on Land and Ocean Ecosystems
FREQUENT MEASUREMENTS OF ATMOSPHERIC CO2 AND OTHER TRACE SPECIES USING COMMERCIAL AIRLINES Description:
A
new research project has started in 2003 to develop Continuous CO2
Measurement Equipment (CME) and
Automatic Air Sampling Equipment (ASE)
for commercial airlines. CMEs are planning to be installed on five aircrafts
and fly to South East Asia, East Asia, Europe, North America, Pacific and Australia.
Routine air sampling by ASE will
be done twice a month between Japan
and Australia.
After issuing the certification, first observation flight by Boeing 747-400
will be conducted in October, 2005. Preliminary observation by small research
aircraft indicates that CME
produces reasonable results.
Filesize: 77.95 Kb Added on: 01-Aug-2005 Downloads: 193 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
DECADAL CHANGES IN OCEAN CARBON UPTAKE Description:
There
is growing evidence that the rate of anthropogenic CO2 uptake in the
ocean is changing over time. Several programs are poised to assess current and
future ocean CO2 uptake rates, but there are issues with how to
extrapolate these measurements to decadal-scale changes over entire ocean
basins. One possibility is to exploit the growing network of ARGO floats that
are collecting profiles throughout the global oceans. We explore the viability
of this approach and make recommendations for how the ARGO network might be
made more useful for biogeochemical applications.
Filesize: 25.55 Kb Added on: 04-Aug-2005 Downloads: 192 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
NEW COUPLED CLIMATE-CARBON SIMULATIONS WITH THE IPSL MODEL: FROM VALIDATION WITH ATMOSPHERIC ... Description: We have developed a
Climate-Carbon coupled model based on the IPSL OAGCM and on two biogeochemical
models, ORCHIDEE for the continent and PISCES for the ocean, to investigate the
coupling between climate change and the global carbon cycle. We have performed
four climate-carbon simulations over the 1860-2100 period in which atmospheric
CO2 is interactively calculated. They are :
§
A control coupled
simulation with no anthropogenic emissions.
§
A coupled
simulation with anthropogenic emissions.
§
A coupled
simulation with anthropogenic emissions including non-CO2 greenhouse
and sulfate aerosols.
§
An uncoupled
carbon simulation with the same anthropogenic emissions as second simulation
but for which atmospheric CO2 change has no impact on climate.
Compared to the first IPSL
Climate-Carbon coupled model [Dufresne,
et al., 2002], the simple carbon models have been replaced by IPSL advanced
ocean and land biogeochemical models, respectively PISCES and ORCHIDEE. CO2
is transported in the atmosphere and compared with observations. Comparison
with satellite data is also done. We then analyze the coupled and uncoupled
simulations, highlight the importance of the climate change both on the oceanic
and biosphere sink and estimate the climate-carbon feedback. The results are
also compared to the outputs of other models participating in the C4MIP
inter-comparison project. Finally, off-line simulations are carried out to
perform sensitivity tests (fire, dynamics of land and ocean ecosystems, soil
respiration) in order to identify the key processes which govern the simulated
response. Filesize: 35.21 Kb Added on: 27-Jul-2005 Downloads: 182 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
EUROPEAN-WIDE REDUCTION IN PRIMARY PRODUCTIVITY CAUSED BY THE HEAT AND DROUGHT IN 2003 Description:
Future climate warming is expected to enhance plant
growth in temperate ecosystems and to increase carbon sequestration. But
although severe regional heatwaves may become more frequent in a changing
climate, and their impact on terrestrial carbon cycling is unclear. Europe experienced a particularly extreme climate anomaly
during 2003, with July temperatures up to 6°C above long-term means, and annual
precipitation deficits up to 300 mmy-1, that is 50% below the
average. We used the 2003 heatwave as a ‘laboratory assistant’ to estimate the
impact on terrestrial carbon cycling.
Filesize: 23.98 Kb Added on: 28-Jul-2005 Downloads: 179 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
ROLE OF AGRICULTURAL MANAGEMENT IN MITIGATING GREENHOUSE EMISSIONS Description: Analyses of
Northern Hemisphere carbon fluxes indicate that a number of ecosystem processes
jointly contribute to source and sink exchanges of CO2 which affect
the net carbon sequestered from the atmosphere. These processes (e.g., CO2,
N2O, CH4, and H2O dynamics) exhibit high
variability in time and space with the largest variability corresponding to
human land management events. Therefore, the spatial and temporal incorporation
of land management information is needed to properly represent net carbon and
other GHG fluxes. Filesize: 34.12 Kb Added on: 03-Aug-2005 Downloads: 174 Home Page | Comment on Proceeding | Details Category: Abstracts/Managing the Carbon Cycle
HAZARDS OF TEMPERATURE ON FOOD AVAILABILITY IN CHANGING ENVIRONMENTS Description: Global
temperatures are predicted to increase from rising
levels of atmospheric carbon dioxide (CO2) and other greenhouse
gases. We conducted experiments in sunlit, controlled-environment chambers and
temperature-gradient greenhouses to determine effects of elevated temperature
and doubled CO2 concentration on pollination and yield of rice,
soybean, dry bean, peanut, and grain sorghum. Photosynthesis and vegetative
growth were more tolerant of increasing temperatures than reproductive
processes. Rice seed yields were optimum at 25°C mean daily temperature and
decreased with increasing temperature (typically about 10% decline for each 1°C
rise in temperature). Grain sorghum yield response to temperature was similar to
rice, but dry bean was more sensitive, and soybean and peanut were more
tolerant. Pollen viability followed a temperature response similar to seed
yield. Comparisons of 43 rice cultivars in temperature-gradient greenhouses
showed genetic variation in percent seed-set in response to a 4.5°C increase
above ambient temperatures in Florida.
Thus, there appears to be a range of adaptation of seed crops to temperature.
Elevated CO2 did not prevent high temperature decline in yield; in
dry bean it made pollination more sensitive to high temperature. In summary, global
warming will be a greater threat to crop seed yields than to photosynthesis and
vegetative growth. However, crop genetic improvements might ameliorate part,
but not all, of the high temperature hazards for seed yields and global food
security.
Filesize: 28.20 Kb Added on: 25-Jul-2005 Downloads: 173 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
PERSISTENCE OF NITROGEN LIMITATION OVER TERRESTRIAL CARBON UPTAKE Description: Because
vegetation growth in the Northern Hemisphere is typically nitrogen-limited,
increased nitrogen deposition could have attenuating effect on rising
atmospheric CO2 by stimulating the accumulation of biomass. Given
the high carbon to nitrogen ratios and long lifetimes of carbon in wood, a most
significant effect of nitrogen fertilization is expected in forests. Forest
inventories indicate that the carbon content of northern forests have increased
concurrently with increased nitrogen deposition since the 1950s [Spiecker et al.,
1996]. In addition, variations in atmospheric CO2 indicate a
globally significant carbon sink in northern mid-latitude forest regions [Schimel et al.,
2001]. It is unclear however, whether elevated nitrogen deposition or other
factors are the primary cause of carbon sequestration in northern forests. We
argue that the elevated nitrogen deposition is unlikely to enhance vegetation
carbon sink significantly because of its differentiating effect on the carbon
sequestration capacity of uneven aged forests and climatic limitations on
carbon sequestration in the Northern Hemisphere. We estimate the potential of
forests with lifted nitrogen limitation to decelerate CO2
concentrations rise in the atmosphere and therefore to mitigate climate
warming. We also outline areas of the Northern Hemisphere which are most
sensitive to increased nitrogen deposition. Filesize: 135.93 Kb Added on: 28-Jul-2005 Downloads: 172 Home Page | Comment on Proceeding | Details | Comments (1) Category: Abstracts/Carbon Cycle Response to Environmental Change
TOP-DOWN REGIONAL CO2 FLUXES FOR NORTH AMERICA ESTIMATED FROM NOAA-CMDL CO2 OBSERVATIONS Description:
We present an analysis of terrestrial net CO2 fluxes from North America for the period 2000-2004. These fluxes
consist of hourly maps at ~70km×100km resolution that are consistent with
observed atmospheric CO2 mixing ratios, as well as with varying
climatic conditions across different ecosystems as observed from space. The
flux maps are created in a newly developed ensemble data assimilation system
that consists of the atmospheric Transport Model v5 (TM5), the Vegetation
Photosynthesis Respiration Model (VPRM), and an efficient Bayesian
least-squares algorithm to optimize the fluxes from different biomes in VPRM
against CO2 mixing ratios from the NOAA-CMDL
observing network. The stochastic nature of the ensemble data assimilation
system allows us to consistently include uncertainty on net CO2 fluxes from the neighboring oceans and more distant continents
in the flux estimates for North America.
Filesize: 364.14 Kb Added on: 03-Aug-2005 Downloads: 167 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
A DECREASING TREND IN NORTHERN HEMISPHERE CARBON UPTAKE SINCE 1992 Description: Increases in the north-south gradient of
atmospheric CO2
at Northern Hemisphere measurement sites of the NOAA/CMDL Global Air Sampling
Network reveal a shrinking carbon sink.
14 of 16 low altitude sites show differences with South Pole increasing
at a faster rate than can be explained by fossil fuel emissions, resulting in
an average north-south difference at remote marine sites nearly 1 ppm larger in
2003 than in 1992. Regardless of whether
this trend will persist, it shows that large changes in the carbon cycle can
occur rapidly and is a strong indication of the tenuous nature of terrestrial
carbon sinks.
Filesize: 89.53 Kb Added on: 02-Aug-2005 Downloads: 165 Home Page | Comment on Proceeding | Details | Comments (2) Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
ESTIMATION OF ATMOSPHERIC CO2 FROM AIRS INFRARED SATELLITE RADIANCES IN THE ECMWF DATA ASSIMILATION Description:
Atmospheric
CO2 concentrations have been obtained from the Atmospheric Infrared
Sounder (AIRS) radiance data within the European Centre for Medium-Range
Weather Forecasts (ECMWF) data assimilation system. In a first explorative
configuration, a subset of channels from the AIRS instrument has been
assimilated providing estimates of tropospheric column-averaged CO2
mixing ratios representative of a layer between the tropopause and about 700
hPa at observation locations only. Results show considerable geographical and
temporal variability with values ranging between 370 and 382 ppmv. The 5-day
mean estimated random error is about 1%, which is confirmed by comparisons with
flask observations on board flights of Japanese airliners in the west-Pacific
region. This study demonstrates the feasibility of global CO2
estimation using high spectral resolution infrared satellite data in a
numerical weather prediction data assimilation system. Currently, the system is
being improved to treat CO2 as a full three-dimensional atmospheric
variable included in the forecast model. This allows more flexibility in the
constraints on the CO2 estimation as well as the possibility of
assimilating other data sources (e.g., near-infrared satellite data and
flasks). The CO2 fields provided by the data assimilation system
have great potential to assist the surface flask network in constraining
current top-down carbon flux estimates.
Filesize: 217.21 Kb Added on: 28-Jul-2005 Downloads: 163 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
A 50 YEAR RECORD OF THE EVOLUTION OF THE MERIDIONAL GRADIENT IN ATMOSPHERIC CO2 AND ITS ... Description:
Measurements of atmospheric CO2 began in
1957-1958 at a wide range of locations, including at fixed stations, on ice
floes, on oceanic expeditions, and on aircraft flights, with logistical and
financial support provided by the International Geophysical Year (IGY) program.
Although the measurement effort was reduced in scope immediately following the
IGY, today, measurements are made at more than 100 locations. Over this same time interval, emissions of CO2
from fossil fuel combustion increased from 2.3 thousand million metric tons per
year (GtC/yr) in 1958 to 7.1 GtC/yr in 2003 [Marland et
al., 2005, and personal communication]. More than 90% of this CO2 was
released into the northern hemisphere where it lingered before mixing fully
world-wide. The atmospheric CO2
concentration, in response, rose faster in the northern hemisphere than in the
southern, the interhemispheric difference increasing from near zero during the
IGY to about 3 parts per million (ppm) in 2003. For all northern hemisphere
stations where our program has measured CO2, the gradient changes
relative to the South Pole are generally proportional to the rate of fossil
fuel CO2 emissions, disregarding seasonal and short term interannual
variability in the CO2 data.
Here, we use this fact to diagnose how the carbon cycle has evolved over
the past half century.
Filesize: 40.33 Kb Added on: 01-Aug-2005 Downloads: 163 Home Page | Comment on Proceeding | Details Category: Abstracts/The Fate of Fossil-Fuel Carbon Emissions
PROPOSING A MECHANISTIC UNDERSTANDING OF ATMOSPHERIC CO2 DURING THE LATE PLEISTOCENE... Description: Paleo-climate records in ice cores revealed high
variability in temperature, atmospheric dust content and carbon dioxide. The
longest CO2 record from the Antarctic ice core of the Vostok station
went back in time as far as about 410 kyr BP showing a switch of glacials and
interglacials in all those parameters approximately every 100 kyr during the
last four glacial cycles with CO2 varying between 180-300 ppmv [Petit et al., 1999]. New measurements of dust and the
isotopic temperature proxy deuterium of the EPICA Dome C (EDC) ice core covered
the last 740 kyr, however, revealed glacial cycles of reduced temperature
amplitude [EPICA community members, 2004]. These
new archives offer the possibility to propose atmospheric CO2 for
the pre-Vostok time span as called for in the EPICA challenge [Wolff et al., 2004]. Here, we contribute to this challenge
using a box model of the isotopic carbon cycle [Köhler et
al., 2005] based on process understanding previously derived for
Termination I. Our results show that major features of the Vostok period are
reproduced while prior to Vostok our model predicts significantly smaller
amplitudes in CO2 variations. Filesize: 48.63 Kb Added on: 01-Aug-2005 Downloads: 163 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
THE POTENTIAL OF UPPER OCEAN ALKALINITY CONTROLS FOR ATMOSPHERIC CARBON DIOXIDE CHANGES Description:
Extreme
global model scenarios of complete preservation and degradation of biogenic
particulate CaCO3 (calcium carbonate) in open ocean waters which are
supersaturated with respect to CaCO3 were carried out. According to
these experiments, the theoretical potential of upper ocean alkalinity controls
for changing the atmospheric pCO2 (CO2 partial pressure)
amounts to several hundred μatm on time scales of several 104 years.
Up to a timescale of 103 years, however, the respective influence is
minor as compared to an expected anthropogenic increase of the atmospheric pCO2
in the order of 500-1000
μatm.
Filesize: 80.15 Kb Added on: 29-Jul-2005 Downloads: 161 Home Page | Comment on Proceeding | Details Category: Abstracts/Impacts of High CO2 on Land and Ocean Ecosystems
INTERANNUAL VARIABILITY IN TERRESTRIAL CARBON EXCHANGE USING AN ECOSYSTEM FIRE MODEL Description: We have incorporated a
semi-mechanistic fire model into the SEVER Dynamic Global Vegetation Model (DGVM).
The model produces estimates of net primary productivity (NPP), heterotrophic
respiration (HR) and fire carbon emission (FE) for the globe. This model was
run for the period 1957-2002 with the NCEP climate reanalysis data as an input.
Results were compared with the ATSR area burnt maps and a Time Dependent
Inverse (TDI) model fluxes of CO2. We find that on interannual time
scales NPP variability explains major part of flux variability simulated by the
TDI model, followed by the HR and FE contributions. Filesize: 64.05 Kb Added on: 08-Aug-2005 Downloads: 161 Home Page | Comment on Proceeding | Details Category: Abstracts/Land Use and the Terrestrial Carbon Cycle
THE CHANGING CARBON CYCLE Description: The carbon cycle has undergone
changes from 1998-2003 as a result of extensive droughts. The CO2 seasonal amplitude at MLO
halted its increase, and the CO2 growth rate accelerated as a result
of a slowing down of the North American carbon sink. In a series of coupled carbon-climate model
experiments, we show a greater probability of drier soils in the 21st
century, especially in the tropics and in mid-latitude summers as
temperature-driven evapotranspiration exceed precipitation, and a positive
feedback between the carbon cycle and climate. This positive feedback reduces
the land and ocean’s capacity to store fossil fuel CO2 and
accelerates the warming. A fossil fuel emission accelerating rapidly as the
sink capacities decrease leads to further increases in the airborne fraction of
fossil fuel CO2.
Filesize: 58.93 Kb Added on: 28-Jul-2005 Downloads: 159 Home Page | Comment on Proceeding | Details | Comments (1) Category: Abstracts/Carbon Cycle Response to Environmental Change
WHAT ARE THE MOST IMPORTANT FACTORS FOR CLIMATE CARBON CYCLE COUPLING Description: Data
from long-term measurements of carbon balance in boreal, mid-latitude and
tropical ecosystems are used to assess the mechanisms that drive changes in
ecosystem carbon balance in response to a changing climate. We find that most
model parameterizations overestimate the temperature sensitivity of ecosystem
respiration and underestimate the role of soil water balance in controlling
respiration and flammability. We conclude that model assessments of
climate—carbon feedbacks must carefully simulate regional precipitation,
evaporation, evapotranspiration, and water balance, including factors leading
to fires (e.g. sources of ignition), in addition to assessing changes in
temperature. Covariances among these drivers of ecosystem respiration and
vegetation change may be critically important for these simulations. Filesize: 686.66 Kb Added on: 09-Aug-2005 Downloads: 158 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
NITROGEN REGULATION OF CARBON SEQUESTRATION IN TERRESTRIAL ECOSYSTEMS IN RESPONSE TO RISING ... Description:
A highly controversial issue in global change
research is the regulation of terrestrial carbon (C) sequestration by soil
nitrogen (N) availability. The Third Assessment IPCC Report predicts rising atmospheric CO2
alone could stimulate terrestrial carbon (C) sequestration by 350 – 980 Pg (=1015
g) C in the 21st Century. Sequestering 350 – 980 Gt C in terrestrial
ecosystems requires 7.7 – 37.5 Pg (N) based on a stoichiochemical relationship
that approximately 0.005 g N is required for 1 g C stored in long-lived plant
biomass (i.e., wood) and 0.067 g N for 1 g C sequestered in soil organic matter
(SOM). Thus, to realistically predict
future C sequestration in terrestrial ecosystems, we have to understand how
closely C and N processes are coupled in response to rising Ca.
Filesize: 24.39 Kb Added on: 01-Aug-2005 Downloads: 157 Home Page | Comment on Proceeding | Details Category: Abstracts/Impacts of High CO2 on Land and Ocean Ecosystems
EFFECTS OF VERTICAL DIC DISTRIBUTION ON STORAGE EFFICIENCY OF DIRECT INJECTION OF CO2 INTO THE OCEAN Description:
We estimated the effects of initial
vertical distribution of dissolved inorganic carbon (DIC) on storage efficiency
of direct injection of CO2 into the ocean. Our simulations shown
that the storage efficiencies could be reduced up to 10% if a relative large
droplet (30 mm in diameter) was injected at depth of 1500m. The storage
efficiency of CO2 ocean sequestration is strongly related with not
only injection depth but also the initial CO2 droplet diameter. With
a given injection rate, the larger droplets injected will produce a dilute DIC
plume and thus improve the acute biological impacts but a smaller storage
effective due to droplet ascending.
Filesize: 204.22 Kb Added on: 28-Jul-2005 Downloads: 155 Home Page | Comment on Proceeding | Details Category: Abstracts/Managing the Carbon Cycle
THE AMAZON AND THE MODERN CARBON CYCLE Description:
Is
the massive Amazon forest a CO2 sink, a source or is it in
equilibrium?
There
is a large uncertainty in carbon fluxes estimates for the tropics as a whole
and in particular for the Amazon region in South America,
bringing the attention to the lack of information to call the region a carbon
source or sink. The production of scientific consistent and long term data
series for the region is a process that has to advance step by step.
Filesize: 35.51 Kb Added on: 03-Aug-2005 Downloads: 155 Home Page | Comment on Proceeding | Details Category: Abstracts/Carbon Cycle Response to Environmental Change
THE AGE OF CARBON RESPIRED FROM TERRESTRIAL ECOSYSTEMS Description: Carbon
enters ecosystems through a single process, photosynthesis, and nearly all is
returned to the atmosphere through respiration, some 50-80% of which occurs
below-ground. Soil (belowground) respiration integrates CO2 derived
from C that has resided in the ecosystem for periods of differing duration,
ranging from relatively recent photosynthetic products that fuel root
metabolism, to CO2 derived from decomposition of plant and soil
organic matter that may be decades to centuries old. A comparison of the radiocarbon content of CO2
respired by roots, microbes, and soils with the record of radiocarbon in
atmospheric CO2 allows direct estimation of the mean age of C being
respired [Trumbore 2000; Wang et al. 2000, Cisneros Dozal et al. 2005; Borken
et al. 2005].
Filesize: 21.45 Kb Added on: 08-Aug-2005 Downloads: 155 Home Page | Comment on Proceeding | Details Category: Abstracts/Land Use and the Terrestrial Carbon Cycle
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Talk History | |
Friday, September 30 | · | Discussion Panel |
· | Nitrogen Regulation of Carbon Sequestration in Terrestrial Ecosystems in Respons |
· | The Role of Water Relations in Driving Grassland Ecosystem Responses to Rising A |
· | Unraveling the Decline in High-latitude Surface Ocean Carbonate |
Thursday, September 29 | · | Hazards of Temperature on Food Availability in Changing Environments (HOT-FACE) |
· | The Amazon and the Modern Carbon Cycle |
· | New Coupled Climate-carbon Simulations from the IPSL Model |
· | The Changing Carbon Cycle |
· | What are the Most Important Factors for Climate-carbon Cycle Coupling? |
· | CO2 Uptake of the Marine Biosphere |
· | European-wide Reduction in Primary Productivity Caused by the Heat and Drought i |
· | Persistence of Nitrogen Limitation over Terrestrial Carbon Uptake |
· | Atmospheric CO2, Carbon Isotopes, the Sun, and Climate Change over the Last Mill |
· | Proposing a Mechanistic Understanding of Atmospheric CO2 During the late Pleist |
· | Greenhouse Gas (CO2, CH4) and Climate Evolution since 650 kyrs Deduced from Anta |
Wednesday, September 28 | · | (In and) Out of Africa: Estimating the Carbon Exchange of a Continent |
· | Recent Shifts in Soil Dynamics on Growing Season Length, Productivity, and... |
· | Interannual Variability in the Carbon Exchange Using an Ecosystem-fire Model |
· | Photosynthesis and Respiration in Forests in Response to Environmental Changes |
· | Seasonal and Interannual Variability in Net Ecosystem CO2 Exchange in Japan |
· | Estimating Landscape-level Carbon Fluxes from Tower CO2 Mixing Ratio Measurement |
· | Monitoring Effects in Climate and Fire Regime on Net Ecosystem Production |
· | Radiative Forcing from a Boreal Forest Fire |
· | The Influence of Soil and Water Management on Carbon Erosion and Burial |
· | Spatial and Temporal Patterns of CO2, CH4, and N2O Fluxes in Ecosystems |
· | Modeling the History of Terrestrial Carbon Sources and Sinks |
· | The Age of Carbon Respired from Terrestrial Ecosystems |
· | Discussion Panel |
· | The Underpinnings of Land Use History |
Tuesday, September 27 | · | Regional CO2 Fluxes for North America Estimated from NOAA/CMDL Observatories |
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