Skip to content. | Skip to navigation

Personal tools

You are here: Home / Publications / Peer-reviewed papers / lmd_Boucher2013_bib.html



@comment{{This file has been generated by bib2bib 1.95}}
@comment{{Command line: /usr/bin/bib2bib --quiet -c 'not journal:"Discussions"' -c 'not journal:"Polymer Science"' -c '  author:"Boucher"  ' -c year=2013 -c $type="ARTICLE" -oc lmd_Boucher2013.txt -ob lmd_Boucher2013.bib /home/WWW/LMD/public/}}
  author = {{Pe{\~n}uelas}, J. and {Poulter}, B. and {Sardans}, J. and {Ciais}, P. and 
	{van der Velde}, M. and {Bopp}, L. and {Boucher}, O. and {Godderis}, Y. and 
	{Hinsinger}, P. and {Llusia}, J. and {Nardin}, E. and {Vicca}, S. and 
	{Obersteiner}, M. and {Janssens}, I.~A.},
  title = {{Human-induced nitrogen-phosphorus imbalances alter natural and managed ecosystems across the globe}},
  journal = {Nature Communications},
  year = 2013,
  month = dec,
  volume = 4,
  eid = {2934},
  pages = {2934},
  abstract = {{The availability of carbon from rising atmospheric carbon dioxide levels
and of nitrogen from various human-induced inputs to ecosystems is
continuously increasing; however, these increases are not paralleled by
a similar increase in phosphorus inputs. The inexorable change in the
stoichiometry of carbon and nitrogen relative to phosphorus has no
equivalent in Earth{\rsquo}s history. Here we report the profound and yet
uncertain consequences of the human imprint on the phosphorus cycle and
nitrogen:phosphorus stoichiometry for the structure, functioning and
diversity of terrestrial and aquatic organisms and ecosystems. A mass
balance approach is used to show that limited phosphorus and nitrogen
availability are likely to jointly reduce future carbon storage by
natural ecosystems during this century. Further, if phosphorus
fertilizers cannot be made increasingly accessible, the crop yields
projections of the Millennium Ecosystem Assessment imply an increase of
the nutrient deficit in developing regions.
  doi = {10.1038/ncomms3934},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Alterskj{\ae}r}, K. and {Kristj{\'a}nsson}, J.~E. and {Boucher}, O. and 
	{Muri}, H. and {Niemeier}, U. and {Schmidt}, H. and {Schulz}, M. and 
	{Timmreck}, C.},
  title = {{Sea-salt injections into the low-latitude marine boundary layer: The transient response in three Earth system models}},
  journal = {Journal of Geophysical Research (Atmospheres)},
  keywords = {climate engineering},
  year = 2013,
  month = nov,
  volume = 118,
  number = d17,
  pages = {12195},
  abstract = {{proposed mechanisms for counteracting global warming through solar
radiation management is the deliberate injection of sea salt acting via
marine cloud brightening and the direct effect of sea-salt aerosols. In
this study, we show results from multidecadal simulations of such
sea-salt climate engineering (SSCE) on top of the RCP4.5 emission
scenario using three Earth system models. As in the proposed ''G3''
experiment of the Geoengineering Model Intercomparison Project, SSCE is
designed to keep the top-of-atmosphere radiative forcing at the 2020
level for 50 years. SSCE is then turned off and the models run for
another 20 years, enabling an investigation of the abrupt warming
associated with a termination of climate engineering (''termination
effect''). As in former idealized studies, the climate engineering in all
three models leads to a significant suppression of evaporation from
low-latitude oceans and reduced precipitation over low-latitude oceans
as well as in the storm-track regions. Unlike those studies, however, we
find in all models enhanced evaporation, cloud formation, and
precipitation over low-latitude land regions. This is a response to the
localized cooling over the low-latitude oceans imposed by the SSCE
design. As a result, the models obtain reduced aridity in many
low-latitude land regions as well as in southern Europe. Terminating the
SSCE leads to a rapid near-surface temperature increase, which, in the
Arctic, exceeds 2 K in all three models within 20 years after SSCE has
ceased. In the same period September Arctic sea ice cover shrinks by
over 25\%.
  doi = {10.1002/2013JD020432},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Kravitz}, B. and {Forster}, P.~M. and {Jones}, A. and {Robock}, A. and 
	{Alterskj{\ae}r}, K. and {Boucher}, O. and {Jenkins}, A.~K.~L. and 
	{Korhonen}, H. and {Kristj{\'a}nsson}, J.~E. and {Muri}, H. and 
	{Niemeier}, U. and {Partanen}, A.-I. and {Rasch}, P.~J. and 
	{Wang}, H. and {Watanabe}, S.},
  title = {{Sea spray geoengineering experiments in the geoengineering model intercomparison project (GeoMIP): Experimental design and preliminary results}},
  journal = {Journal of Geophysical Research (Atmospheres)},
  keywords = {Geoengineering, Model Intercomparison, Marine Clouds},
  year = 2013,
  month = oct,
  volume = 118,
  number = d17,
  pages = {11175},
  abstract = {{cloud brightening through sea spray injection has been proposed as a
method of temporarily alleviating some of the impacts of anthropogenic
climate change, as part of a set of technologies called geoengineering.
We outline here a proposal for three coordinated climate modeling
experiments to test aspects of sea spray geoengineering, to be conducted
under the auspices of the Geoengineering Model Intercomparison Project
(GeoMIP). The first, highly idealized, experiment (G1ocean-albedo)
involves a uniform increase in ocean albedo to offset an instantaneous
quadrupling of CO$_{2}$ concentrations from preindustrial levels.
Results from a single climate model show an increased land-sea
temperature contrast, Arctic warming, and large shifts in annual mean
precipitation patterns. The second experiment (G4cdnc) involves
increasing cloud droplet number concentration in all low-level marine
clouds to offset some of the radiative forcing of an RCP4.5 scenario.
This experiment will test the robustness of models in simulating
geographically heterogeneous radiative flux changes and their effects on
climate. The third experiment (G4sea-salt) involves injection of sea
spray aerosols into the marine boundary layer between 30{\deg}S and
30{\deg}N to offset 2 W m$^{-2}$ of the effective radiative forcing
of an RCP4.5 scenario. A single model study shows that the induced
effective radiative forcing is largely confined to the latitudes in
which injection occurs. In this single model simulation, the forcing due
to aerosol-radiation interactions is stronger than the forcing due to
aerosol-cloud interactions.
  doi = {10.1002/jgrd.50856},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Tilmes}, S. and {Fasullo}, J. and {Lamarque}, J.-F. and {Marsh}, D.~R. and 
	{Mills}, M. and {Alterskj{\ae}r}, K. and {Muri}, H. and {Kristj{\'a}nsson}, J.~E. and 
	{Boucher}, O. and {Schulz}, M. and {Cole}, J.~N.~S. and {Curry}, C.~L. and 
	{Jones}, A. and {Haywood}, J. and {Irvine}, P.~J. and {Ji}, D. and 
	{Moore}, J.~C. and {Karam}, D.~B. and {Kravitz}, B. and {Rasch}, P.~J. and 
	{Singh}, B. and {Yoon}, J.-H. and {Niemeier}, U. and {Schmidt}, H. and 
	{Robock}, A. and {Yang}, S. and {Watanabe}, S.},
  title = {{The hydrological impact of geoengineering in the Geoengineering Model Intercomparison Project (GeoMIP)}},
  journal = {Journal of Geophysical Research (Atmospheres)},
  keywords = {geoengineering, hydrological cycle, climate change, GeoMIP, solar radiation management, monsoon},
  year = 2013,
  month = oct,
  volume = 118,
  number = d17,
  pages = {11036},
  abstract = {{The hydrological impact of enhancing Earth's albedo by solar radiation
management is investigated using simulations from 12 Earth System models
contributing to the Geoengineering Model Intercomparison Project
(GeoMIP). We contrast an idealized experiment, G1, where the global mean
radiative forcing is kept at preindustrial conditions by reducing
insolation while the CO$_{2}$ concentration is quadrupled to a
4{\times}CO$_{2}$ experiment. The reduction of evapotranspiration
over land with instantaneously increasing CO$_{2}$ concentrations
in both experiments largely contributes to an initial reduction in
evaporation. A warming surface associated with the transient adjustment
in 4{\times}CO$_{2}$ generates an increase of global precipitation
by around 6.9\% with large zonal and regional changes in both directions,
including a precipitation increase of 10\% over Asia and a reduction of
7\% for the North American summer monsoon. Reduced global evaporation
persists in G1 with temperatures close to preindustrial conditions.
Global precipitation is reduced by around 4.5\%, and significant
reductions occur over monsoonal land regions: East Asia (6\%), South
Africa (5\%), North America (7\%), and South America (6\%). The general
precipitation performance in models is discussed in comparison to
observations. In contrast to the 4{\times}CO$_{2}$ experiment,
where the frequency of months with heavy precipitation intensity is
increased by over 50\% in comparison to the control, a reduction of up to
20\% is simulated in G1. These changes in precipitation in both total
amount and frequency of extremes point to a considerable weakening of
the hydrological cycle in a geoengineered world.
  doi = {10.1002/jgrd.50868},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Jones}, A. and {Haywood}, J.~M. and {Alterskj{\ae}r}, K. and 
	{Boucher}, O. and {Cole}, J.~N.~S. and {Curry}, C.~L. and {Irvine}, P.~J. and 
	{Ji}, D. and {Kravitz}, B. and {Egill-Kristj{\'a}nsson}, J. and 
	{Moore}, J.~C. and {Niemeier}, U. and {Robock}, A. and {Schmidt}, H. and 
	{Singh}, B. and {Tilmes}, S. and {Watanabe}, S. and {Yoon}, J.-H.
  title = {{The impact of abrupt suspension of solar radiation management (termination effect) in experiment G2 of the Geoengineering Model Intercomparison Project (GeoMIP)}},
  journal = {Journal of Geophysical Research (Atmospheres)},
  keywords = {geoengineering, termination, climate change, climate model, intercomparison, GeoMIP},
  year = 2013,
  month = sep,
  volume = 118,
  pages = {9743-9752},
  abstract = {{We have examined changes in climate which result from the sudden
termination of geoengineering after 50 years of offsetting a 1\% per
annum increase in CO$_{2}$ concentrations by a reduction of solar
radiation, as simulated by 11 different climate models in experiment G2
of the Geoengineering Model Intercomparison Project. The models agree on
a rapid increase in global-mean temperature following termination
accompanied by increases in global-mean precipitation rate and decreases
in sea-ice cover. There is no agreement on the impact of geoengineering
termination on the rate of change of global-mean plant net primary
productivity. There is a considerable degree of consensus for the
geographical distribution of temperature change following termination,
with faster warming at high latitudes and over land. There is also
considerable agreement regarding the distribution of reductions in
Arctic sea-ice, but less so for the Antarctic. There is much less
agreement regarding the patterns of change in precipitation and net
primary productivity, with a greater degree of consensus at higher
  doi = {10.1002/jgrd.50762},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Kravitz}, B. and {Caldeira}, K. and {Boucher}, O. and {Robock}, A. and 
	{Rasch}, P.~J. and {Alterskj{\ae}R}, K. and {Karam}, D.~B. and 
	{Cole}, J.~N.~S. and {Curry}, C.~L. and {Haywood}, J.~M. and 
	{Irvine}, P.~J. and {Ji}, D. and {Jones}, A. and {Kristj{\'a}Nsson}, J.~E. and 
	{Lunt}, D.~J. and {Moore}, J.~C. and {Niemeier}, U. and {Schmidt}, H. and 
	{Schulz}, M. and {Singh}, B. and {Tilmes}, S. and {Watanabe}, S. and 
	{Yang}, S. and {Yoon}, J.-H.},
  title = {{Climate model response from the Geoengineering Model Intercomparison Project (GeoMIP)}},
  journal = {Journal of Geophysical Research (Atmospheres)},
  keywords = {geoengineering, model intercomparison},
  year = 2013,
  month = aug,
  volume = 118,
  pages = {8320-8332},
  abstract = {{geoengineering{\mdash}deliberate reduction in the amount of solar
radiation retained by the Earth{\mdash}has been proposed as a means of
counteracting some of the climatic effects of anthropogenic greenhouse
gas emissions. We present results from Experiment G1 of the
Geoengineering Model Intercomparison Project, in which 12 climate models
have simulated the climate response to an abrupt quadrupling of
CO$_{2}$ from preindustrial concentrations brought into radiative
balance via a globally uniform reduction in insolation. Models show this
reduction largely offsets global mean surface temperature increases due
to quadrupled CO$_{2}$ concentrations and prevents 97\% of the
Arctic sea ice loss that would otherwise occur under high CO$_{2}$
levels but, compared to the preindustrial climate, leaves the tropics
cooler (-0.3 K) and the poles warmer (+0.8 K). Annual mean precipitation
minus evaporation anomalies for G1 are less than 0.2 mm day$^{-1}$
in magnitude over 92\% of the globe, but some tropical regions receive
less precipitation, in part due to increased moist static stability and
suppression of convection. Global average net primary productivity
increases by 120\% in G1 over simulated preindustrial levels, primarily
from CO$_{2}$ fertilization, but also in part due to reduced plant
heat stress compared to a high CO$_{2}$ world with no
geoengineering. All models show that uniform solar geoengineering in G1
cannot simultaneously return regional and global temperature and
hydrologic cycle intensity to preindustrial levels.
  doi = {10.1002/jgrd.50646},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Huneeus}, N. and {Boucher}, O. and {Chevallier}, F.},
  title = {{Atmospheric inversion of SO$_{2}$ and primary aerosol emissions for the year 2010}},
  journal = {Atmospheric Chemistry \& Physics},
  year = 2013,
  month = jul,
  volume = 13,
  pages = {6555-6573},
  abstract = {{Natural and anthropogenic emissions of primary aerosols and sulphur
dioxide (SO$_{2}$) are estimated for the year 2010 by assimilating
daily total and fine mode aerosol optical depth (AOD) at 550 nm from the
Moderate Resolution Imaging Spectroradiometer (MODIS) satellite
instrument into a global aerosol model of intermediate complexity. The
system adjusts monthly emission fluxes over a set of predefined regions
tiling the globe. The resulting aerosol emissions improve the model
performance, as measured from usual skill scores, both against the
assimilated observations and a set of independent ground-based
measurements. The estimated emission fluxes are 67 Tg S yr$^{-1}$
for SO$_{2}$, 12 Tg yr$^{-1}$ for black carbon (BC), 87 Tg
yr$^{-1}$ for particulate organic matter (POM), 17 000 Tg
yr$^{-1}$ for sea salt (SS, estimated at 80 \% relative humidity)
and 1206 Tg yr$^{-1}$ for desert dust (DD). They represent a
difference of +53, +73, +72, +1 and -8\%, respectively, with respect to
the first guess (FG) values. Constant errors throughout the regions and
the year were assigned to the a priori emissions. The analysis errors
are reduced with respect to the a priori ones for all species and
throughout the year, they vary between 3 and 18\% for SO$_{2}$, 1
and 130\% for biomass burning, 21 and 90 \% for fossil fuel, 1 and 200\%
for DD and 1 and 5\% for SS. The maximum errors on the global-yearly
scale for the estimated fluxes (considering temporal error dependence)
are 3\% for SO$_{2}$, 14\% for BC, 11\% for POM, 14\% for DD and 2\%
for SS. These values represent a decrease as compared to the
global-yearly errors from the FG of 7\% for SO$_{2}$, 40\% for BC,
55\% for POM, 81\% for DD and 300\% for SS. The largest error reduction,
both monthly and yearly, is observed for SS and the smallest one for
SO$_{2}$. The sensitivity and robustness of the inversion system
to the choice of the first guess emission inventory is investigated by
using different combinations of inventories for industrial, fossil fuel
and biomass burning sources. The initial difference in the emissions
between the various set-ups is reduced after the inversion. Furthermore,
at the global scale, the inversion is sensitive to the choice of the BB
(biomass burning) inventory and not so much to the industrial and fossil
fuel inventory. At the regional scale, however, the choice of the
industrial and fossil fuel inventory can make a difference. The
estimated baseline emission fluxes for SO$_{2}$, BC and POM are
within the estimated uncertainties of the four experiments. The
resulting emissions were compared against projected emissions for the
year 2010 for SO$_{2}$, BC and POM. The new estimate presents
larger emissions than the projections for all three species, with larger
differences for SO$_{2}$ than POM and BC. These projected
SO$_{2}$ emissions are outside the uncertainties of the estimated
emission inventories.
  doi = {10.5194/acp-13-6555-2013},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Otto}, A. and {Otto}, F.~E.~L. and {Boucher}, O. and {Church}, J. and 
	{Hegerl}, G. and {Forster}, P.~M. and {Gillett}, N.~P. and {Gregory}, J. and 
	{Johnson}, G.~C. and {Knutti}, R. and {Lewis}, N. and {Lohmann}, U. and 
	{Marotzke}, J. and {Myhre}, G. and {Shindell}, D. and {Stevens}, B. and 
	{Allen}, M.~R.},
  title = {{Energy budget constraints on climate response}},
  journal = {Nature Geoscience},
  year = 2013,
  month = jun,
  volume = 6,
  pages = {415-416},
  doi = {10.1038/ngeo1836},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Ménégoz}, M. and {Krinner}, G. and {Balkanski}, Y. and 
	{Cozic}, A. and {Boucher}, O. and {Ciais}, P.},
  title = {{Boreal and temperate snow cover variations induced by black carbon emissions in the middle of the 21st century}},
  journal = {The Cryosphere},
  year = 2013,
  month = mar,
  volume = 7,
  pages = {537-554},
  abstract = {{We used a coupled climate-chemistry model to quantify the impacts of
aerosols on snow cover north of 30{\deg} N both for the present-day and
for the middle of the 21st century. Black carbon (BC) deposition over
continents induces a reduction in the mean number of days with snow at
the surface (MNDWS) that ranges from 0 to 10 days over large areas of
Eurasia and Northern America for the present-day relative to the
pre-industrial period. This is mainly due to BC deposition during the
spring, a period of the year when the remaining of snow accumulated
during the winter is exposed to both strong solar radiation and a large
amount of aerosol deposition induced themselves by a high level of
transport of particles from polluted areas. North of 30{\deg} N, this
deposition flux represents 222 Gg BC month$^{-1}$ on average from
April to June in our simulation. A large reduction in BC emissions is
expected in the future in all of the Representative Concentration
Pathway (RCP) scenarios. In particular, considering the RCP8.5 in our
simulation leads to a decrease in the spring BC deposition down to 110
Gg month$^{-1}$ in the 2050s. However, despite the reduction of
the aerosol impact on snow, the MNDWS is strongly reduced by 2050, with
a decrease ranging from 10 to 100 days from present-day values over
large parts of the Northern Hemisphere. This reduction is essentially
due to temperature increase, which is quite strong in the RCP8.5
scenario in the absence of climate mitigation policies. Moreover, the
projected sea-ice retreat in the next decades will open new routes for
shipping in the Arctic. However, a large increase in shipping emissions
in the Arctic by the mid-21st century does not lead to significant
changes of BC deposition over snow-covered areas in our simulation.
Therefore, the MNDWS is clearly not affected through snow darkening
effects associated with these Arctic ship emissions. In an experiment
without nudging toward atmospheric reanalyses, we simulated however some
changes of the MNDWS considering such aerosol ship emissions. These
changes are generally not statistically significant in boreal
continents, except in Quebec and in the West Siberian plains, where they
range between -5 and -10 days. They are induced both by radiative
forcings of the aerosols when they are in the snow and in the
atmosphere, and by all the atmospheric feedbacks. These experiments do
not take into account the feedbacks induced by the interactions between
ocean and atmosphere as they were conducted with prescribed sea surface
temperatures. Climate change by the mid-21st century could also cause
biomass burning activity (forest fires) to become more intense and occur
earlier in the season. In an idealised scenario in which forest fires
are 50\% stronger and occur 2 weeks earlier and later than at present, we
simulated an increase in spring BC deposition of 21 Gg BC
month$^{-1}$ over continents located north of 30{\deg} N. This BC
deposition does not impact directly the snow cover through snow
darkening effects. However, in an experiment considering all the aerosol
forcings and atmospheric feedbacks, except those induced by the
ocean-atmosphere interactions, enhanced fire activity induces a
significant decrease of the MNDWS reaching a dozen of days in Quebec and
in Eastern Siberia.
  doi = {10.5194/tc-7-537-2013},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Stier}, P. and {Schutgens}, N.~A.~J. and {Bellouin}, N. and 
	{Bian}, H. and {Boucher}, O. and {Chin}, M. and {Ghan}, S. and 
	{Huneeus}, N. and {Kinne}, S. and {Lin}, G. and {Ma}, X. and 
	{Myhre}, G. and {Penner}, J.~E. and {Randles}, C.~A. and {Samset}, B. and 
	{Schulz}, M. and {Takemura}, T. and {Yu}, F. and {Yu}, H. and 
	{Zhou}, C.},
  title = {{Host model uncertainties in aerosol radiative forcing estimates: results from the AeroCom Prescribed intercomparison study}},
  journal = {Atmospheric Chemistry \& Physics},
  year = 2013,
  month = mar,
  volume = 13,
  pages = {3245-3270},
  abstract = {{Simulated multi-model ''diversity'' in aerosol direct radiative forcing
estimates is often perceived as a measure of aerosol uncertainty.
However, current models used for aerosol radiative forcing calculations
vary considerably in model components relevant for forcing calculations
and the associated ''host-model uncertainties'' are generally convoluted
with the actual aerosol uncertainty. In this AeroCom Prescribed
intercomparison study we systematically isolate and quantify host model
uncertainties on aerosol forcing experiments through prescription of
identical aerosol radiative properties in twelve participating models.

Even with prescribed aerosol radiative properties, simulated clear-sky and all-sky aerosol radiative forcings show significant diversity. For a purely scattering case with globally constant optical depth of 0.2, the global-mean all-sky top-of-atmosphere radiative forcing is -4.47 Wm$^{-2}$ and the inter-model standard deviation is 0.55 Wm$^{-2}$, corresponding to a relative standard deviation of 12\%. For a case with partially absorbing aerosol with an aerosol optical depth of 0.2 and single scattering albedo of 0.8, the forcing changes to 1.04 Wm$^{-2}$, and the standard deviation increases to 1.01 W$^{-2}$, corresponding to a significant relative standard deviation of 97\%. However, the top-of-atmosphere forcing variability owing to absorption (subtracting the scattering case from the case with scattering and absorption) is low, with absolute (relative) standard deviations of 0.45 Wm$^{-2}$ (8\%) clear-sky and 0.62 Wm$^{-2}$ (11\%) all-sky.

Scaling the forcing standard deviation for a purely scattering case to match the sulfate radiative forcing in the AeroCom Direct Effect experiment demonstrates that host model uncertainties could explain about 36\% of the overall sulfate forcing diversity of 0.11 Wm$^{-2}$ in the AeroCom Direct Radiative Effect experiment.

Host model errors in aerosol radiative forcing are largest in regions of uncertain host model components, such as stratocumulus cloud decks or areas with poorly constrained surface albedos, such as sea ice. Our results demonstrate that host model uncertainties are an important component of aerosol forcing uncertainty that require further attention. }}, doi = {10.5194/acp-13-3245-2013}, adsurl = {}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }
  author = {{Woodhouse}, M.~T. and {Mann}, G.~W. and {Carslaw}, K.~S. and 
	{Boucher}, O.},
  title = {{Sensitivity of cloud condensation nuclei to regional changes in dimethyl-sulphide emissions}},
  journal = {Atmospheric Chemistry \& Physics},
  year = 2013,
  month = mar,
  volume = 13,
  pages = {2723-2733},
  abstract = {{The atmospheric oxidation of dimethyl-sulphide (DMS) derived from marine
phytoplankton is a significant source of marine sulphate aerosol. DMS
has been proposed to regulate climate via changes in cloud properties,
though recent studies have shown that present-day global cloud
condensation nuclei (CCN) concentrations have only a weak dependence on
the total emission flux of DMS. Here, we use a global aerosol
microphysics model to examine how efficiently CCN are produced when DMS
emissions are changed in different marine regions. We find that global
CCN production per unit mass of sulphur emitted varies by more than a
factor of 20 depending on where the change in oceanic DMS emission flux
is applied. The variation in CCN production efficiency depends upon
where CCN production processes (DMS oxidation, SO$_{2}$ oxidation,
nucleation and growth) are most efficient and removal processes
(deposition) least efficient. The analysis shows that the production of
aerosol sulphate through aqueous-phase oxidation of SO$_{2}$
limits the amount of H$_{2}$SO$_{4}$ available for
nucleation and condensational growth and therefore suppresses CCN
formation, leading to the weak response of CCN to changes in DMS
emission. Our results show that past and future changes in the spatial
distribution of DMS emissions (through changes in the phytoplankton
population or wind speed patterns) could exert a stronger control on
climate than net increases in biological productivity.
  doi = {10.5194/acp-13-2723-2013},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Folland}, C.~K. and {Colman}, A.~W. and {Smith}, D.~M. and 
	{Boucher}, O. and {Parker}, D.~E. and {Vernier}, J.-P.},
  title = {{High predictive skill of global surface temperature a year ahead}},
  journal = {\grl},
  keywords = {prediction},
  year = 2013,
  month = feb,
  volume = 40,
  pages = {761-767},
  abstract = {{We discuss 13 real-time forecasts of global annual-mean surface
temperature issued by the United Kingdom Met Office for 1 year ahead for
2000-2012. These involve statistical, and since 2008, initialized
dynamical forecasts using the Met Office DePreSys system. For the period
when the statistical forecast system changed little, 2000-2010, issued
forecasts had a high correlation of 0.74 with observations and a root
mean square error of 0.07{\deg}C. However, the HadCRUT data sets against
which issued forecasts were verified were biased slightly cold,
especially from 2004, because of data gaps in the strongly warming
Arctic. This observational cold bias was mainly responsible for a
statistically significant warm bias in the 2000-2010 forecasts of
0.06{\deg}C. Climate forcing data sets used in the statistical method,
and verification data, have recently been modified, increasing hindcast
correlation skill to 0.80 with no significant bias. Dynamical hindcasts
for 2000-2011 have a similar correlation skill of 0.78 and skillfully
hindcast annual mean spatial global surface temperature patterns. Such
skill indicates that we have a good understanding of the main factors
influencing global mean surface temperature.
  doi = {10.1002/grl.50169},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Bellouin}, N. and {Quaas}, J. and {Morcrette}, J.-J. and {Boucher}, O.
  title = {{Estimates of aerosol radiative forcing from the MACC re-analysis}},
  journal = {Atmospheric Chemistry \& Physics},
  year = 2013,
  month = feb,
  volume = 13,
  pages = {2045-2062},
  abstract = {{The European Centre for Medium-range Weather Forecast (ECMWF) provides
an aerosol re-analysis starting from year 2003 for the Monitoring
Atmospheric Composition and Climate (MACC) project. The re-analysis
assimilates total aerosol optical depth retrieved by the Moderate
Resolution Imaging Spectroradiometer (MODIS) to correct for model
departures from observed aerosols. The re-analysis therefore combines
satellite retrievals with the full spatial coverage of a numerical
model. Re-analysed products are used here to estimate the shortwave
direct and first indirect radiative forcing of anthropogenic aerosols
over the period 2003-2010, using methods previously applied to satellite
retrievals of aerosols and clouds. The best estimate of
globally-averaged, all-sky direct radiative forcing is -0.7 {\plusmn} 0.3
Wm$^{-2}$. The standard deviation is obtained by a Monte-Carlo
analysis of uncertainties, which accounts for uncertainties in the
aerosol anthropogenic fraction, aerosol absorption, and cloudy-sky
effects. Further accounting for differences between the present-day
natural and pre-industrial aerosols provides a direct radiative forcing
estimate of -0.4 {\plusmn} 0.3 Wm$^{-2}$. The best estimate of
globally-averaged, all-sky first indirect radiative forcing is -0.6
{\plusmn} 0.4 Wm$^{-2}$. Its standard deviation accounts for
uncertainties in the aerosol anthropogenic fraction, and in cloud albedo
and cloud droplet number concentration susceptibilities to aerosol
changes. The distribution of first indirect radiative forcing is
asymmetric and is bounded by -0.1 and -2.0 Wm$^{-2}$. In order to
decrease uncertainty ranges, better observational constraints on aerosol
absorption and sensitivity of cloud droplet number concentrations to
aerosol changes are required.
  doi = {10.5194/acp-13-2045-2013},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Boucher}, O. and {Quaas}, J.},
  title = {{Water vapour affects both rain and aerosol optical depth}},
  journal = {Nature Geoscience},
  year = 2013,
  month = jan,
  volume = 6,
  pages = {4-5},
  doi = {10.1038/ngeo1692},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
Contact information

EMC3 group

Case 99
Tour 45-55, 3ème étage
4 Place Jussieu
75252 Paris Cedex 05
Tel: 33 + 1 44 27 27 99
      33 + 6 16 27 34 18 (Dr F. Cheruy)
Tel: 33 + 1 44 27 35 25 (Secretary)
Fax: 33 + 1 44 27 62 72
email: emc3 at

Map of our location

Real time LMDZ simulations

Today's LMDZ meteogram for the SIRTA site

Intranet EMC3

Intranet EMC3