F. Hourdin, F. Forget, C. Hourdin and O. Talagrand
Laboratoire de Météorologie Dynamique du CNRS, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05, FranceS.R. Lewis, P.L. Read and F.W. Taylor
University of Oxford, Atmospheric, Oceanic and Planetary Physics, Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United KingdomM.A. Lopez-Valverde, M. Lopez-Puertas
Instituto de Astrofisica de Andalucia (CSIC), c/ Camino Bajo de Huetor, 24, Apartado 3004, 18080 Granada, SpainThis proposal requests new funding to support an extension to the European Space Agency Contract No. 11369/95/NL/JG, Martian Environment Models, which has been undertaken jointly by Laboratoire de Météorologie Dynamique of CNRS/Ecole Normale Supérieure, Paris, France (hereafter LMD) and Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford, United Kingdom (hereafter AOPP). Under the original contract an advanced general circulation model of the Martian atmosphere was developed and sets of multi-annual simulations were conducted by both contractors in order to compile a database of climate statistics for use in future engineering studies. The final version of the model, database, software to access the database and related documentation were delivered at the end of the contract period. Under a first extension the models were further reviewed and improved and substantial changes were made to the representation of variability in the climate database.
This proposal seeks further support in order to test, improve and extend the products of the contract so far. The current model will be improved in important respects relating to the introduction of an improved parameterization of non-LTE radiation so that the model top may be raised for the climate integrations and by improvements to the treatment of interactive dust transport, sources and sinks.
In connection with the development of non-LTE code, it is proposed to extend the spread of expertise of our groups by inviting the participation of Drs. Lopez-Valverde and Lopez-Puertas from the Instituto de Astrofisica de Andalucia (IAA), CISC, Granada, Spain, in the new phase of the programme. The group in Granada are internationally leading experts in non-LTE effects on radiative transfer in the atmospheres of the terrestrial planets, and have in the past developed advanced numerical models for making accurate spectral computations of radiative transfer in the upper atmospheres of Earth and Mars. Although such models are impracticably expensive for direct use in a general circulation model, it is proposed to make use of dedicated computations to be carried out by the Granada group to validate the new radiative transfer parameterizations to be developed as part of this phase of the project. In addition, the Granada group will contribute their expertise towards improving the design of the new parameterization schemes, particularly with regard to the inclusion of non-LTE effects important at high altitudes on both Mars and Venus.
The Mars model will be validated against the latest spacecraft data available and the re-tuned model will be used to compile a third version of the Mars Climate Database. This will be compiled using a model incorporating all the improvements produced under this contract including the raised model top and interactive dust transport. The database will make use of the improved two-dimensional variability model generated under WP5 of the contract, applied to the latest model data. Wherever improvements to the model and database software come to light as a result of further testing and use, software will be made available to ESA and installed at the end of the extended contract period.
The viability of extending the methodology developed under this contract to building a climate model for Venus will be reported upon. Valuable experience has already been gained within the group in the construction of advanced models of the atmosphere of a terrestrial planet and the compilation of a climate database, using novel statistical techniques, from model output. The atmosphere of Venus has a similar composition to that of Mars, which determines key properties such as the radiative field. The radiative problems we are proposing to deal with as part of this proposal, such as the non-LTE parameterizations, present similarities between the planets and common approaches may be taken in their study. Given that we have all the European expertise in place for this contract, the opportunity will be taken to write a review of the current knowledge of the atmosphere of Venus and to discuss the possibility of producing a climate database in the future in order to assist with planning future spacecraft missions, such as the ESA Venus Sample Return proposal.
The following work packages, in two deliverable stages, are proposed to be added to the existing ESA Contract, No. 11369/95/NL/JG. The packages are proposed to improve and to extend the General Circulation Model and Climate Database developed under that contract and to consider extensions of the work to produce similar products in future for the atmosphere of Venus.
The General Conditions (Part II) of the original contract will continue to apply without further changes.