WRF Model Prediction of a Dense Fog Event Occurred During the Winter Fog Experiment (WIFEX)
Pithani, Prakash ; Ghude, Sachin D. ; Chennu, V.N. ; Kulkarni, Rachana G. ; Steeneveld, Gert Jan ; Sharma, Ashish ; Prabhakaran, Thara ; Chate, D.M. ; Gultepe, Ismail ; Jenamani, R.K. ; Madhavan, Rajeevan - \ 2019
Pure and Applied Geophysics 176 (2019)4. - ISSN 0033-4553 - p. 1827 - 1846.
Liquid water content - PBL scheme - vertical level - WIFEX - WRF model
In this study, the sensitivity of the Weather Research and Forecasting (WRF) model to simulate the life cycle of a dense fog event that occurred on 23–24 January 2016 is evaluated using different model configurations. For the first time, intensive observational periods (IOPs) were made during the unique winter fog experiment (WIFEX) that took place over Delhi, India, where air quality is serious during the winter months. The multiple sensitivity experiments to evaluate the WRF model performance included parameters such as initial model and boundary conditions, vertical resolution in the lower boundary layer (BL), and the planetary BL (PBL) physical parameterizations. In addition, the model sensitivity was tested using various configurations that included domain size and grid resolution. Results showed that simulations with a high number of vertical levels within the lower PBL height (i.e., 10 levels below 300 m) simulated the accurate timing of fog formation, development, and dissipation. On the other hand, simulations with less vertical levels in the PBL captured only the mature physical characteristics of the fog cycle. A comparison of six local PBL schemes showed little variation in the onset of fog life cycle in comparison to observations of visibility. However, comparisons of observations with thermodynamical values such as 2-m temperature and longwave radiation showed poor relationships. Overall, quasi-normal scale elimination (QNSE) and MYNN 2.5 PBL schemes simulated the complete fog life cycle correctly with high liquid water content (LWC; 0.5/0.35 g m −3 ), while other schemes only responded during the mature phase.
The politics of IWRM in Southern Africa
Mehta, L. ; Alba, R. ; Bolding, J.A. ; Denby, K. ; Derman, B. ; Hove, T. ; Manzungu, E. ; Movik, S. ; Prabhakaran, P. ; Koppen, B.M.C. - \ 2014
International Journal of Water Resources Development 30 (2014)3. - ISSN 0790-0627 - p. 528 - 542.
water-resources management - catchment management - developing-countries - zimbabwe - lessons
This article offers an approach to the study of the evolution, spread and uptake of integrated water resources management (IWRM). Specifically, it looks at the flow of IWRM as an idea in international and national fora, its translation and adoption into national contexts, and the on-the-ground practices of IWRM. Research carried out in South Africa, Zimbabwe and Mozambique provides empirical insights into the politics of IWRM implementation in southern Africa, the interface between international and national interests in shaping water policies in specific country contexts, and the on-the-ground challenges of addressing equity, redress and the reallocation of water.