The works carried out during the first year of my DPhil project are presented in this report. The objective of this project is to make use of a unique and advanced data assimilation system that enables the combining of observational data with predictions from a global numerical model of the Martian atmospheric circulation. In this report, an introduction to the planet Mars and a brief descripti...

The development of data assimilation techniques for numerical weather prediction has been very successful ever since the early 1950s until now, starting with simple two-dimensional and univariate spatial interpolation techniques like the successive corrections (SC, Bergthorsson and Döös, 1955) ending up with the four-dimensional variational data assimilation (4D-Var, Rabier et al., 2000) and en...

Title of dissertation: INFORMATION FLOW IN AN ATMOSPHERIC MODEL AND DATA ASSIMILATION Young-noh Yoon, Doctor of Philosophy, 2011 Dissertation directed by: Professor Edward Ott Department of Physics Weather forecasting consists of two processes, model integration and analysis (data assimilation). During the model integration, the state estimate produced by the analysis evolves to the next cycle ...

Data assimilation refers to the statistical techniques used to combine numerical and statistical models with observations to give an improved estimate of the state of a system or process. Typically a data assimilation problem has a sequential aspect where data as it becomes available over time is used to update the state or parameters of a dynamical system. Data assimilation is usually distingu...

It is well documented that immigrants are in better health upon arrival in the United States than their American counterparts, but that this health advantage erodes over time. We study the potential determinants of this “healthy immigrant effect”, with a particular focus on the tendency of immigrants to converge to unhealthy American BMI levels. Using data from the National Health Interview Sur...

Plants differ in tissue localization of nitrate reduction and assimilation. Some species reduce nitrate primarily in the leaves, whereas other species localize nitrate reduction and assimilation in the roots. We determined how nitrate assimilation is partitioned among leaves, stems and roots of poplar (Populus tremula L. x P. alba L.) by comparing tissue differences in in vivo nitrate reductase...

1. The effect of nitrate reduction and assimilation on the CO(2)/O(2) quotient of gas exchange has been used as an index of the relative rates of carbon and nitrogen assimilation in Chlorella pyrenoidosa. Changes in over-all metabolism induced by starvation, high light intensity, and nitrogen deficiency have been studied in comparison with the metabolism of cells growing at light-limiting inten...

The impact of dark NH(4) (+) and NO(3) (-) assimilation on photosynthetic light harvesting capability of the green alga Selenastrum minutum was monitored by chlorophyll a fluorescence analysis. When cells assimilated NH(4) (+), they exhibited a large decline in the variable fluorescence/maximum fluorescence ratio, the fluorescence yield of photosystem II relative to that of photosystem I at 77 ...

An integrated approach to modeling atmospheric chemistry with trace gas data assimilation is a relatively new focus of the atmospheric chemistry modeling community. It is expected that the predictive capability of CTMs can be significantly improved by assimilating measurements of key trace gases from satellite-based platforms and surface monitors. Ensemble adjustment Kalman filter (EAKF) method...