May 19, 2015

The spatial and temporal evolution of contributing areas: Nippgen et'al, 2015

I am always interested on the representation of topography and their conditioning into the hydrological modelling. I have seen this accepted paper of Brian McGlynn and his co-workers entitled "The spatial and temporal evolution of contributing area". At the moment, I didn't go through it  but the topic is very  interesting, so I am saving to my list to read papers. The introduction section (objective of the paper ) reads as follows:

"Here we present a parsimonious but fully distributed modeling framework that incorporates topographically driven lateral water redistribution and eddy covariance derived spatially disaggregated evapotranspiration measurements to simulate streamflow and the spatial distribution of water stored in the watershed through time. The goal of the model development and this particular application was to inform our understanding of the spatial and temporal dynamics of runoff source areas. Utilizing and testing this diagnostic modeling framework in conjunction with empirical measurements of hillslope connectivity through an extensive network of shallow groundwater wells [Jencso et al., 2009; 2010; Jencso and McGlynn, 2011] we approximated watershed connectivity to investigate how runoff source areas change in space and time over the course of two water years in a snowmelt dominated system."

May 7, 2015

Albedo for snow dynamics study

Albedo, the measure of surface reflectivity, is the key physical data that we can exploit for different purpose.  For instance, it is useful to understand the snow hydrology, which relatively suffers from the luck of ground measurements, to understand the dynamics of state. Recently, we were interested if we can use this information in this direction, and I have seen this post and it take my attention. "ICE SHEET DARKENING" .  Here is the link, you can read the whole story yourself. "You know There's something Wrong When vast expanses of Greenland Look Like A Blackened Volcanic Creater". It is amazing to see that the change in albedo of the Greenland  just in a decade is about 6%. 

Rainfall animation: for fun

Following the R codes provided by Arnold Salvacion , here is the rainfall animation map that I estimated  for Ethiopia, from long term  WorldClim  monthly precipitation dataset.  WorldClim is a set of global climate layers (climate grids) with a spatial resolution of about 1 square kilometer.  So the essence of this animation is  rainfall data spatially averaged at zonal level, and temporally averaged at monthly level ( i.e long term monthly mean). The maps are at zonal administrative level. 

Reclaiming Agenda

Reading a book "The Motivational Manifesto" by Brendon Burchard, he mentioned that one of the important characteristics of high achiever, in whatsoever work (or field), is the claim of  agenda of life, and clarity on the purpose of their work. It is true that life with no clear agenda could not be a charged life. This is even more applicable in research that, spending fraction of time here and there, and diffuse attention allover, does not help a researcher to be high achiever.  As young hydrologist, I tends  to wonder around in many aspect of the subject, of course to those interesting too learn, but that probably would limit my achievement and research result production. Though it is early to clearly define my life time research agenda, I would like to start tune to some of the following general subjects:
  • Understanding  hydrological processes ( rainfall-runoff processes, Evapotranspiration processes, ecohydrology) 
  • Estimating water balance at the basin scale (all the sciences and efforts to improve estimation of water cycle components such as remote sensing, interpolation skills, data assimilation)
  • Understanding the interaction of Vegetation-Geomorphology-Hydrology (Eco-Hydro-Geomorphology )
  • Excel in the use of tools and program(ing) languages  that are important for spatial analysis such as GIS, R, and Java. 
Of course they all are interrelated.