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# lmd_all2001.bib

@comment{{This file has been generated by bib2bib 1.98}}

@comment{{Command line: /usr/bin/bib2bib --quiet -c 'not journal:"Discussions"' -c 'not journal:"Polymer Science"' -c year=2001 -c $type="ARTICLE" -oc lmd_all2001.txt -ob lmd_all2001.bib ./EMC3all.link.bib}}  @article{2001JGR...10628113B, author = {{Bonazzola}, M. and {Picon}, L. and {Laurent}, H. and {Hourdin}, F. and {SèZe}, G. and {Pawlowska}, H. and {Sadourny}, R.}, title = {{Retrieval of large-scale wind divergences from infrared Meteosat-5 brightness temperatures over the Indian Ocean}}, journal = {\jgr}, keywords = {Meteorology and Atmospheric Dynamics: Convective processes, Meteorology and Atmospheric Dynamics: General circulation, Meteorology and Atmospheric Dynamics: Numerical modeling and data assimilation, Meteorology and Atmospheric Dynamics: Tropical meteorology}, year = 2001, month = nov, volume = 106, pages = {28113}, abstract = {{Over the tropics the atmospheric general circulation models usually fail in predicting horizontal wind divergence, which is closely related to atmospheric heating and to the vertical exchanges associated with convection. With the aim of forcing atmospheric models we present here a reconstruction of wind divergences based on the links between infrared brightness temperatures, convective activity, and large-scale divergence. In practice, wind divergences are reconstructed from brightness temperatures using correlations obtained from numerical simulations performed with a general circulation model. When building those correlations, a distinction must be made between the brightness temperatures of opaque clouds and those of semitransparent clouds, only the former being directly associated with convection. In order to filter out semitransparent clouds we use radiative thresholds in the water vapor channel in addition to the window channel. We apply our approach to Meteosat-5 data over the Indian Ocean. Comparison with wind divergences reconstructed independently from Meteosat water vapor winds partially validates our retrieval. Comparison with European Center for Medium-Range Weather Forecasts analyses indicates that much can be gained by adding information on the wind divergence in the tropics to force an atmospheric model. }}, doi = {10.1029/2000JD900690}, adsurl = {http://adsabs.harvard.edu/abs/2001JGR...10628113B}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001JCli...14..730C, author = {{Codron}, F. and {Vintzileos}, A. and {Sadourny}, R.}, title = {{Influence of Mean State Changes on the Structure of ENSO in a Tropical Coupled GCM.}}, journal = {Journal of Climate}, year = 2001, month = mar, volume = 14, pages = {730-742}, abstract = {{This study examines the response of the climate simulated by the Institut Pierre Simon Laplace tropical Pacific coupled general circulation model to two changes in parameterization: an improved coupling scheme at the coast, and the introduction of a saturation mixing ratio limiter in the water vapor advection scheme, which improves the rainfall distribution over and around orography. The main effect of these modifications is the suppression of spurious upwelling off the South American coast in Northern Hemisphere summer. Coupled feedbacks then extend this warming over the whole basin in an El Ni{\~n}o-like structure, with a maximum at the equator and in the eastern part of the basin. The mean precipitation pattern widens and moves equatorward as the trade winds weaken.This warmer mean state leads to a doubling of the standard deviation of interannual SST anomalies, and to a longer ENSO period. The structure of the ENSO cycle also shifts from westward propagation in the original simulation to a standing oscillation. The simulation of El Ni{\~n}o thus improves when compared to recent observed events. The study of ENSO spatial structure and lagged correlations shows that these changes of El Ni{\~n}o characteristics are caused by both the increase of amplitude and the modification of the spatial structure of the wind stress response to SST anomalies.These results show that both the mean state and variability of the tropical ocean can be very sensitive to biases or forcings, even geographically localized. They may also give some insight into the mechanisms responsible for the changes in ENSO characteristics due to decadal variability or climate change. }}, doi = {10.1175/1520-0442(2001)014<0730:IOMSCO>2.0.CO;2}, adsurl = {http://adsabs.harvard.edu/abs/2001JCli...14..730C}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001JGR...10628427L, author = {{Leon}, J.-F. and {Chazette}, P. and {Dulac}, F. and {Pelon}, J. and {Flamant}, C. and {Bonazzola}, M. and {Foret}, G. and {Alfaro}, S.~C. and {Cachier}, H. and {Cautenet}, S. and {Hamonou}, E. and {Gaudichet}, A. and {Gomes}, L. and {Rajot}, J.-L. and {Lavenu}, F. and {Inamdar}, S.~R. and {Sarode}, P.~R. and {Kadadevarmath}, J.~S.}, title = {{Large-scale advection of continental aerosols during INDOEX}}, journal = {\jgr}, keywords = {Atmospheric Composition and Structure: Aerosols and particles, Atmospheric Composition and Structure: Pollution-urban and regional, Atmospheric Composition and Structure: Troposphere-constituent transport and chemistry, Meteorology and Atmospheric Dynamics: Remote sensing}, year = 2001, month = nov, volume = 106, pages = {28427}, abstract = {{In this paper, we present passive and active remote sensing measurements of atmospheric aerosols over the North Indian Ocean (NIO) during the Intensive Field Phase (IFP, January to March 1999) of the Indian Ocean Experiment. The variability of the aerosol load over NIO is discussed based on three-dimentional numerical simulations made at a local scale by use of Regional Atmospheric Modeling System (RAMS) and at a regional scale using the zoomed Laboratoire de Météorologie Dynamique global circulation model (LMD-Z version 3.3). Ground-based measurements of the columnar aerosol optical thickness (AOT) and of surface black carbon (BC) concentration were carried out at two different sites in India: Goa University on the NIO coast and Dharwar 150 km inland. Local-scale investigations point out that the trend in BC concentration at the ground is not correlated with AOT. Lidar profiles obtained both from the surface at Goa and in the NIO from the Mystere-20 research aircraft indicate that a significant contribution to the total AOT (more than 50\%) is due to a turbid monsoon layer located between 1 and 3 km height. RAMS simulation shows that the advection of aerosols in the monsoon layer is due to the conjunction of land-sea breeze and topography. We present the regional-scale extent of the aerosol plume in terms of AOT derived from the visible channel of Meteosat-5. During March, most of the Bay of Bengal is overcast by a haze with a monthly average AOT of 0.61{\plusmn}0.18, and a spatially well-defined aerosol plume is spreading from the Indian west coast to the Intertropical Convergence Zone with an average AOT of 0.49{\plusmn}0.08. Those values are bigger than in February with AOT at 0.35{\plusmn}0.18 and 0.37{\plusmn}0.09 for the Bay of Bengal and the Arabian Sea, respectively. One of the principal findings of this paper is that a significant contribution to the aerosol load over the NIO is due to the advection of continental aerosols from India in a well-identified monsoon layer above the marine boundary layer. Moreover, it is suggested that the increase in biomass burning plays a significant role in the increasing trend in AOT during the winter dry monsoon season. }}, doi = {10.1029/2001JD900023}, adsurl = {http://adsabs.harvard.edu/abs/2001JGR...10628427L}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001JGR...10628415S, author = {{SèZe}, G. and {Pawlowska}, H.}, title = {{Cloud cover analysis with METEOSAT-5 during INDOEX}}, journal = {\jgr}, keywords = {Meteorology and Atmospheric Dynamics: Climatology, Meteorology and Atmospheric Dynamics: Remote sensing, Meteorology and Atmospheric Dynamics: Tropical meteorology}, year = 2001, month = nov, volume = 106, pages = {28415}, abstract = {{During the Indian Ocean Experiment (INDOEX), METEOSAT-5 positioned at 63{\deg}E provided observation of the visible and infrared radiance field over the Indian Ocean. A cloud classification process using the dynamic cluster method is applied to these data. For the 3 months of the experiment (January-March 1999), daily maps of the cloud cover type are built for 0730 and 0900 UTC. The occurrence frequency of clear sky, low- and high-level cloud cover is examined. These frequencies are compared to the International Satellite Cloud Climatology Program (ISCCP) D1 data set for the period 1984 to 1994. The Indian Ocean region can be classified in three zones. In the north subtropics, clear sky and small cumulus occur at least 90\% of the time. Near the coast of India, clear sky is as frequent as 80 to 100\%. The Intertropical Convergence Zone, characterized by the occurrence frequency of high-level clouds greater than 30\%, spreads from Indonesia to North Madagascar. Near Indonesia, high-level cloud cover occurs more than 55\% of the time. In the south subtropics, low cloud cover is the most frequent. In the eastern part the occurrence frequency reaches 80\%. This percentage decreases along the western side of the ocean where low clouds break up. Between the African coast and Madagascar, high-level clouds are frequent. The mean spatial features found are in agreement with the ISCCP climatology, except for the eastern part of the south subtropics. A regional comparison shows the difficulty of making the analysis of interannual variations of cloud cover obtained from various cloud cover retrievals applied to different satellite data sets. This difficulty arises from the nonneglectable percentage of satellite pixels which can contain some very small low clouds. }}, doi = {10.1029/2001JD900097}, adsurl = {http://adsabs.harvard.edu/abs/2001JGR...10628415S}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001JGR...10628371R, author = {{Ramanathan}, V. and {Crutzen}, P.~J. and {Lelieveld}, J. and {Mitra}, A.~P. and {Althausen}, D. and {Anderson}, J. and {Andreae}, M.~O. and {Cantrell}, W. and {Cass}, G.~R. and {Chung}, C.~E. and {Clarke}, A.~D. and {Coakley}, J.~A. and {Collins}, W.~D. and {Conant}, W.~C. and {Dulac}, F. and {Heintzenberg}, J. and {Heymsfield}, A.~J. and {Holben}, B. and {Howell}, S. and {Hudson}, J. and {Jayaraman}, A. and {Kiehl}, J.~T. and {Krishnamurti}, T.~N. and {Lubin}, D. and {McFarquhar}, G. and {Novakov}, T. and {Ogren}, J.~A. and {Podgorny}, I.~A. and {Prather}, K. and {Priestley}, K. and {Prospero}, J.~M. and {Quinn}, P.~K. and {Rajeev}, K. and {Rasch}, P. and {Rupert}, S. and {Sadourny}, R. and {Satheesh}, S.~K. and {Shaw}, G.~E. and {Sheridan}, P. and {Valero}, F.~P.~J.}, title = {{Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze}}, journal = {\jgr}, keywords = {Atmospheric Composition and Structure: Aerosols and particles, Global Change: Atmosphere, Global Change: Climate dynamics, Meteorology and Atmospheric Dynamics: Radiative processes}, year = 2001, month = nov, volume = 106, pages = {28371}, abstract = {{Every year, from December to April, anthropogenic haze spreads over most of the North Indian Ocean, and South and Southeast Asia. The Indian Ocean Experiment (INDOEX) documented this Indo-Asian haze at scales ranging from individual particles to its contribution to the regional climate forcing. This study integrates the multiplatform observations (satellites, aircraft, ships, surface stations, and balloons) with one- and four-dimensional models to derive the regional aerosol forcing resulting from the direct, the semidirect and the two indirect effects. The haze particles consisted of several inorganic and carbonaceous species, including absorbing black carbon clusters, fly ash, and mineral dust. The most striking result was the large loading of aerosols over most of the South Asian region and the North Indian Ocean. The January to March 1999 visible optical depths were about 0.5 over most of the continent and reached values as large as 0.2 over the equatorial Indian ocean due to long-range transport. The aerosol layer extended as high as 3 km. Black carbon contributed about 14\% to the fine particle mass and 11\% to the visible optical depth. The single-scattering albedo estimated by several independent methods was consistently around 0.9 both inland and over the open ocean. Anthropogenic sources contributed as much as 80\% ({\plusmn}10\%) to the aerosol loading and the optical depth. The in situ data, which clearly support the existence of the first indirect effect (increased aerosol concentration producing more cloud drops with smaller effective radii), are used to develop a composite indirect effect scheme. The Indo-Asian aerosols impact the radiative forcing through a complex set of heating (positive forcing) and cooling (negative forcing) processes. Clouds and black carbon emerge as the major players. The dominant factor, however, is the large negative forcing (-20{\plusmn}4 W m$^{-2}$) at the surface and the comparably large atmospheric heating. Regionally, the absorbing haze decreased the surface solar radiation by an amount comparable to 50\% of the total ocean heat flux and nearly doubled the lower tropospheric solar heating. We demonstrate with a general circulation model how this additional heating significantly perturbs the tropical rainfall patterns and the hydrological cycle with implications to global climate. }}, doi = {10.1029/2001JD900133}, adsurl = {http://adsabs.harvard.edu/abs/2001JGR...10628371R}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001JAtS...58.3158B, author = {{Bony}, S. and {Emanuel}, K.~A.}, title = {{A Parameterization of the Cloudiness Associated with Cumulus Convection; Evaluation Using TOGA COARE Data.}}, journal = {Journal of Atmospheric Sciences}, year = 2001, month = nov, volume = 58, pages = {3158-3183}, abstract = {{A new parameterization of the cloudiness associated with cumulus convection is proposed for use in climate models. It is based upon the idea that the convection scheme predicts the local concentration of condensed water (the in-cloud water content) produced at the subgrid scale, and that a statistical cloud scheme predicts how this condensed water is spatially distributed within the domain. The cloud scheme uses a probability distribution function (PDF) of the total water whose variance and skewness coefficient are diagnosed from the amount of condensed water produced at the subgrid scale by cumulus convection and at the large scale by supersaturation, from the degree of saturation of the environment, and from the lower bound of the total water distribution that is taken equal to zero.This parameterization is used in a single-column model forced by the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) data, and including the cumulus convection scheme of Emanuel whose humidity prediction has been optimized using these data. Simulations are carried out during the 120 days of operation of the TOGA COARE intensive observation period. The model is able to reproduce some of the main characteristics of the cloudiness observed over the warm pool. This includes the occurrence of different populations of clouds (shallow, midlevel, and deep convective), a minimum cloud cover between 600 and 800 hPa, some relationship between the distribution of cloud tops and the presence of stable atmospheric layers, the formation of long-lasting upper-tropospheric anvils associated with the maturation of the convective cloud systems, and the presence of an extensive layer of thin cirrus clouds just below the tropopause. Nevertheless, shallow-level clouds are likely to be underestimated. The behavior of the predicted cloud fields is consistent with some statistical features suggested by cloud-resolving model simulations of tropical cloud systems over oceans. The radiative fluxes calculated interactively by the model from the predicted profiles of humidity, temperature, and clouds are in reasonable agreement with satellite data. Sea surface temperatures predicted by the model using its own radiative and turbulent fluxes calculated at the ocean surface differ from observations by a few tenths of a degree.Sensitivity tests show that the performance of the cloudiness parameterization does not critically depend upon the choice of the PDF. On the other hand, they show that the prediction of radiative fluxes is improved when the statistical moments of the PDF are predicted from both large-scale variables and subgrid-scale convective activity rather than from large-scale variables only. }}, doi = {10.1175/1520-0469(2001)058<3158:APOTCA>2.0.CO;2}, adsurl = {http://adsabs.harvard.edu/abs/2001JAtS...58.3158B}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001Icar..152..384L, author = {{Lebonnois}, S. and {Toublanc}, D. and {Hourdin}, F. and {Rannou}, P. }, title = {{Seasonal Variations of Titan's Atmospheric Composition}}, journal = {\icarus}, year = 2001, month = aug, volume = 152, pages = {384-406}, abstract = {{In order to investigate seasonal variations of the composition of Titan's low stratosphere, we developed a two-dimensional (latitude-altitude) photochemical and transport model. Large-scale advection, hidden in the vertical eddy diffusion for one-dimensional models, is accounted for explicitly. Atmospheric dynamics is prescribed using results of independent numerical simulations of the atmospheric general circulation. Both the mean meridional transport and latitudinal mixing by transient planetary waves are taken into account. Chemistry is based on 284 reactions involving 40 hydrocarbons and nitriles. Photodissociation rates are based on a three-dimensional description of the ultraviolet flux. For most species, the model fits well the latitudinal variations observed by Voyager I giving for the first time a full and self-consistent interpretation of these observations. In particular, the enrichment of the high northern latitudes is attributed to subsidence during the winter preceeding the Voyager encounter. Discrepancies are observed for C$_{2}$H$_{4}$, HC$_{3}$N, and C$_{2}$N$_{2}$and are attributed to problems in the chemical scheme. Sensitivity to dynamical parameters is investigated. The vertical eddy diffusion coefficient keeps an important role for the upper atmosphere. The wind strength and horizontal eddy diffusion strongly control the latitudinal behavior of the composition in the low stratosphere, while mean concentrations appear to be essentially controlled by chemistry. }}, doi = {10.1006/icar.2001.6632}, adsurl = {http://adsabs.harvard.edu/abs/2001Icar..152..384L}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001GeoRL..28.1543F, author = {{Friedlingstein}, P. and {Bopp}, L. and {Ciais}, P. and {Dufresne}, J.-L. and {Fairhead}, L. and {LeTreut}, H. and {Monfray}, P. and {Orr}, J. }, title = {{Positive feedback between future climate change and the carbon cycle}}, journal = {\grl}, keywords = {Atmospheric Composition and Structure: Biosphere/atmosphere interactions, Global Change, Oceanography: Biological and Chemical: Carbon cycling}, year = 2001, volume = 28, pages = {1543-1546}, abstract = {{Future climate change due to increased atmospheric CO$_{2}$may affect land and ocean efficiency to absorb atmospheric CO$_{2}$. Here, using climate and carbon three-dimensional models forced by a 1\% per year increase in atmospheric CO$_{2}$, we show that there is a positive feedback between the climate system and the carbon cycle. Climate change reduces land and ocean uptake of CO$_{2}$, respectively by 54\% and 35\% at 4 {\times} CO$_{2}$. This negative impact implies that for prescribed anthropogenic CO$_{2}$emissions, the atmospheric CO$_{2}$would be higher than the level reached if climate change does not affect the carbon cycle. We estimate the gain of this climate-carbon cycle feedback to be 10\% at 2 {\times} CO$_{2}$and 20\% at 4 {\times} CO$_{2}$. This translates into a 15\% higher mean temperature increase. }}, doi = {10.1029/2000GL012015}, adsurl = {http://adsabs.harvard.edu/abs/2001GeoRL..28.1543F}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001E&PSL.187...83Q;, author = {{Qiang}, X.~K. and {Li}, Z.~X. and {Powell}, C.~M. and {Zheng}, H.~B. }, title = {{Magnetostratigraphic record of the Late Miocene onset of the East Asian monsoon, and Pliocene uplift of northern Tibet}}, journal = {Earth and Planetary Science Letters}, year = 2001, month = apr, volume = 187, pages = {83-93}, abstract = {{Widespread eolian red clay underlying the Plio-Pleistocene loess-palaeosol succession in northern China has been dated magnetostratigraphically back to 8.35 Ma, indicating that the East Asian monsoon started at about the same time as the Indian monsoon. An initial sedimentation rate of 11 m/Myr increased gradually to 17.5 m/Myr by 6 Ma, and then decreased to 6 m/Myr between 5 Ma and 3.5 Ma. A marked increase in sedimentation rate and grain size beginning between 3.5 Ma and 3.1 Ma indicates that the East Asian winter monsoon strengthened at this time, and intensified further after 2.6 Ma. The temporal coincidence of the stronger winter monsoon and the Pliocene uplift of northwestern Tibet just before the onset of the Northern Hemisphere glaciation indicate that the three events could be causally linked. }}, doi = {10.1016/S0012-821X(01)00281-3}, adsurl = {http://adsabs.harvard.edu/abs/2001E%26PSL.187...83Q}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001PCEB...26..155L, author = {{Li}, Z.~X.}, title = {{Thermodynamic Air-Sea Interactions and Tropical Atlantic SST Dipole Pattern}}, journal = {Physics and Chemistry of the Earth B}, year = 2001, month = jan, volume = 26, pages = {155-157}, doi = {10.1016/S1464-1909(00)00233-1}, adsurl = {http://adsabs.harvard.edu/abs/2001PCEB...26..155L}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001MWRv..129.1500L, author = {{Liberti}, G.~L. and {Chéruy}, F. and {Desbois}, M.}, title = {{Land Effect on the Diurnal Cycle of Clouds over the TOGA COARE Area, as Observed from GMS IR Data}}, journal = {Monthly Weather Review}, year = 2001, volume = 129, pages = {1500}, doi = {10.1175/1520-0493(2001)129<1500:LEOTDC>2.0.CO;2}, adsurl = {http://adsabs.harvard.edu/abs/2001MWRv..129.1500L}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }  @article{2001ClDy...18..297B, author = {{Boucher}, O. and {Haywood}, J.}, title = {{On summing the components of radiative forcing of climate change}}, journal = {Climate Dynamics}, year = 2001, volume = 18, pages = {297-302}, abstract = {{Radiative forcing is a useful concept in determining the potential influence of a particular mechanism of climate change. However, due to the increased number of forcing agents identified over the past decade, the total radiative forcing is difficult to assess. By assigning a range of probability distribution functions to the individual radiative forcings and using a Monte-Carlo approach, we estimate the total radiative forcing since pre-industrial times including all quantitative radiative forcing estimates to date. The resulting total radiative forcing has a 75-97\% probability of being positive (or similarly a 3-25\% probability of being negative), with mean radiative forcing ranging from +0.68 to +1.34Wm$^{-2}$, and median radiative forcing ranging from +0.94 to +1.39Wm$^{-2}\$.
}},
doi = {10.1007/s003820100185},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@article{2001ClDy...18...29I,
author = {{Ide}, K. and {Le Treut}, H. and {Li}, Z.-X. and {Ghil}, M.},
title = {{Atmospheric radiative equilibria. Part II: bimodal solutions for atmospheric optical properties}},
journal = {Climate Dynamics},
year = 2001,
volume = 18,
pages = {29-49},
abstract = {{A simple theoretical model of atmospheric radiative equilibrium is
solved analytically to help understand the energetics of maintaining
Earth's tropical and subtropical climate. The model climate is
constrained by energy balance between shortwave (SW) and longwave (LW)
radiative fluxes. Given a complete set of SW and LW optical properties
in each atmospheric layer, the model yields a unique
equilibrium-temperature profile. In contrast, if the atmospheric
temperature profile and SW properties are prescribed, the model yields
essentially two distinct LW transmissivity profiles. This bimodality is
due to a nonlinear competition between the ascending and descending
energy fluxes, as well as to their local conversion to sensible heat in
the atmosphere. Idealized slab models that are often used to describe
the greenhouse effect are shown to be a special case of our model when
this nonlinearity is suppressed. In this special case, only one solution
for LW transmissivity is possible. Our model's bimodality in LW
transmissivity for given SW fluxes and temperature profile may help
explain certain features of Earth's climate: at low latitudes the
temperature profiles are fairly homogeneous, while the humidity profiles
exhibit a bimodal distribution; one mode is associated with regions of
moist-and-ascending, the other with dry-and-subsiding air. The model's
analytical results show good agreement with the European Centre for
Medium-Range Weather Forecasts' reanalysis data. Sensitivity analysis of
the temperature profile with respect to LW transmissivity changes leads
to an assessment of the low-latitude climate's sensitivity to the
runaway greenhouse'' effect.
}},
doi = {10.1007/s003820100168},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@article{2001ClDy...17..905W,
author = {{Webb}, M. and {Senior}, C. and {Bony}, S. and {Morcrette}, J.-J.
},
title = {{Combining ERBE and ISCCP data to assess clouds in the Hadley Centre, ECMWF and LMD atmospheric climate models}},
journal = {Climate Dynamics},
year = 2001,
volume = 17,
pages = {905-922},
abstract = {{This study compares radiative fluxes and cloudiness fields from three
Unified model, cycle 16r2 of the ECMWF model and version LMDZ 2.0 of the
LMD GCM), using a combination of satellite observations from the Earth
Radiation Budget Experiment (ERBE) and the International Satellite Cloud
Climatology Project (ISCCP). To facilitate a meaningful comparison with
the ISCCP C1 data, values of column cloud optical thickness and cloud
top pressure are diagnosed from the models in a manner consistent with
the satellite view from space. Decomposing the cloud radiative effect
into contributions from low-medium- and high-level clouds reveals a
tendency for the models' low-level clouds to compensate for
underestimates in the shortwave cloud radiative effect caused by a lack
of high-level or mid-level clouds. The low clouds fail to compensate for
the associated errors in the longwave. Consequently, disproportionate
errors in the longwave and shortwave cloud radiative effect in models
may be taken as an indication that compensating errors are likely to be
present. Mid-level cloud errors in the mid-latitudes appear to depend as
much on the choice of the convection scheme as on the cloud scheme.
Convective and boundary layer mixing schemes require as much
consideration as cloud and precipitation schemes when it comes to
assessing the simulation of clouds by models. Two distinct types of
cloud feedback are discussed. While there is reason to doubt that
current models are able to simulate potential cloud regime' type
feedbacks with skill, there is hope that a model capable of simulating
potential cloud amount' type feedbacks will be achievable once the
reasons for the remaining differences between the models are understood.
}},
doi = {10.1007/s003820100157},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@article{2001ClDy...17..219M,
author = {{Menéndez}, C.~G. and {Saulo}, A.~C. and {Li}, Z.-X.},
title = {{Simulation of South American wintertime climate with a nesting system}},
journal = {Climate Dynamics},
year = 2001,
volume = 17,
pages = {219-231},
abstract = {{A numerical nesting system is developed to simulate wintertime climate
of the eastern South Pacific-South America-western South Atlantic
region, and preliminary results are presented. The nesting system
consists of a large-scale global atmospheric general circulation model
(GCM) and a regional climate model (RCM). The latter is driven at its
boundaries by the GCM. The particularity of this nesting system is that
the GCM itself has a variable horizontal resolution (stretched grid).
Our main purpose is to assess the plausibility of such a technique to
improve climate representation over South America. In order to evaluate
how this nesting system represents the main features of the regional
circulation, several mean fields have been analyzed. The global model,
despite its relatively low resolution, could simulate reasonably well
the more significant large-scale circulation patterns. The use of the
regional model often results in improvements, but not universally. Many
of the systematic errors of the global model are also present in the
regional model, although the biases tend to be rectified. Our
preliminary results suggest that nesting technique is a computationally
low-cost alternative for simulating regional climate features. However,
additional simulations, parametrizations tuning and further diagnosis
are clearly needed to represent local patterns more precisely.
}},
doi = {10.1007/s003820000107},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@article{2001ClDy...17..187C,
author = {{Codron}, F.},
title = {{Sensitivity of the tropical Pacific to a change of orbital forcing in two versions of a coupled GCM}},
journal = {Climate Dynamics},
year = 2001,
volume = 17,
pages = {187-203},
abstract = {{The changes of the variability of the tropical Pacific ocean forced by a
shift of six months in the date of the perihelion are studied using a
coupled tropical Pacific ocean/global atmosphere GCM. The sensitivity
experiments are conducted with two versions of the atmospheric model,
varied by two parametrization changes. The first one concerns the
interpolation scheme between the atmosphere and ocean models grids near
the coasts, the second one the advection of water vapor in the presence
of downstream negative temperature gradients, as encountered in the
vicinity of mountains. In the tropical Pacific region, the
parametrization differences only have a significant direct effect near
the coasts; but coupled feedbacks lead to a 1{\deg}C warming of the
equatorial cold tongue in the modified (version 2) model, and a widening
of the western Pacific large-scale convergence area. The sensitivity of
the seasonal cycle of equatorial SST is very different between the two
experiments. In both cases, the response to the solar flux forcing is
strongly modified by coupled interactions between the SST, wind stress
response and ocean dynamics. In the first version, the main feedback is
due to anomalous upwelling and leads to westward propagation of SST
anomalies; whereas the version 2 model is dominated by an
eastward-propagating thermocline mode. The main reason diagnosed for
these different behaviors is the atmospheric response to SST anomalies.
In the warmer climate simulated by the second version, the wind stress
response in the western Pacific is enhanced, and the off-equatorial curl
is reduced, both effects favoring eastward propagation through
thermocline depth anomalies. The modifications of the simulated seasonal
cycle in version 2 lead to a change in ENSO behavior. In the control
climate, the interannual variability in the eastern Pacific is dominated
by warm events, whereas cold events tend to be the more extreme ones
with a shifted perihelion.
}},
doi = {10.1007/s003820000103},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@article{2001AdSpR..27.1851C,
author = {{Chassefière}, E. and {Forget}, F. and {Hourdin}, F. and
{Vial}, F. and {Rème}, H. and {Mazelle}, C. and {Vignes}, D. and
{Sauvaud}, J.-A. and {Blelly}, P.-L. and {Toublanc}, D. and
{Berthelier}, J.-J. and {Cerisier}, J.-C. and {Chanteur}, G. and
{Duvet}, L. and {Menvielle}, M. and {Lilensten}, J. and {Witasse}, O. and
{Touboul}, P. and {Quèmerais}, E. and {Bertaux}, J.-L. and
{Hulot}, G. and {Cohen}, Y. and {Lognonné}, P. and {Barriot}, J.~P. and
{Balmino}, G. and {Blanc}, M. and {Pinet}, P. and {Parrot}, M. and
{Trotignon}, J.-G. and {Moncuquet}, M. and {Bougeret}, J.-L. and
{Issautier}, K. and {Lellouch}, E. and {Meyer}, N. and {Sotin}, C. and
{Grasset}, O. and {Barlier}, F. and {Berger}, C. and {Tarits}, P. and
{Dyment}, J. and {Breuer}, D. and {Spohn}, T. and {P{\"a}tzold}, M. and
{Sperveslage}, K. and {Gough}, P. and {Buckley}, A. and {Szego}, K. and
{Sasaki}, S. and {Smrekar}, S. and {Lyons}, D. and {Acuna}, M. and
{Connerney}, J. and {Purucker}, M. and {Lin}, R. and {Luhmann}, J. and
{Mitchell}, D. and {Leblanc}, F. and {Johnson}, R. and {Clarke}, J. and
{Nagy}, A. and {Young}, D. and {Bougher}, S. and {Keating}, G. and
{Haberle}, R. and {Jakosky}, B. and {Hodges}, R. and {Parmentier}, M. and
{Waite}, H. and {Bass}, D.},
title = {{Scientific objectives of the DYNAMO mission}},
journal = {Advances in Space Research},
year = 2001,
volume = 27,
pages = {1851-1860},
abstract = {{DYNAMO is a small Mars orbiter planned to be launched in 2005 or 2007,
in the frame of the NASA/ CNES Mars exploration program. It is aimed at
improving gravity and magnetic field resolution, in order to better
understand the magnetic, geologic and thermal history of Mars, and at
characterizing current atmospheric escape, which is still poorly
constrained. These objectives are achieved by using a low periapsis
orbit, similar to the one used by the Mars Global Surveyor spacecraft
during its aerobraking phases. The proposed periapsis altitude for
DYNAMO of 120-130 km, coupled with the global distribution of periapses
to be obtained during one Martian year of operation, through about 5000
low passes, will produce a magnetic/gravity field data set with
approximately five times the spatial resolution of MGS. Additional data
on the internal structure will be obtained by mapping the electric
conductivity. Low periapsis provides a unique opportunity to investigate
the chemical and dynamical properties of the deep ionosphere,
thermosphere, and the interaction between the atmosphere and the solar
wind, therefore atmospheric escape, which may have played a crucial role
in removing atmosphere and water from the planet.
}},
doi = {10.1016/S0273-1177(01)00338-6},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

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