Tutorials Data Himalaya
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| − | + | The soil parameter file is one of the important parameter files which needs a range of information to produce a comprehensive characterization regarding water holding capacity of different soil types. For this, the texture information of soil types of different soil horizons are required. A detailed description of how to produce soil parameter file is provided here: | |
| + | How to create soil parameter file | ||
===Land cover parameter file=== | ===Land cover parameter file=== | ||
Revision as of 09:31, 8 August 2012
The tutorial is prepared to use the J2000 hydrological model for hydrological system analysis of a river catchment. A test catchment and dataset of the Dudh Kosi river basin has been provided with the detailed description to prepare those dataset. The statement of problems, motivation, objectives and methodological apporach for the study area and the rational of using the J2000 model in the study area are also presented. The users can use the data to get familiar with the model application. At the same time, users can prepare their own dataset to understand the hydrological system dynamics of any river basin.
The example dataset presented here is from the Dudh Kosi river basin in the Himalayan region. The model application was used as a part of the PhD research study which can be accessed from the following link: PhD Thesis
The information provided here is largely based on this study.
Contents |
Who can use the tutorial
The tutorial is prepared in such a way that the J2000 hydrological model can be used independently without any techtical support from model developers. Therefore, it can be used by students, model developers and researchers for the hydrological system analysis of a catchment. The tutorial should be read in conjunction with other sub-tutorials which has been mentioned in different part of this tutorial. Additionally, the tutorial is supplied with test dataset of the Dudh Kosi river basin (Nepal, 2012) which users can use to get familiar with the different aspects of the J2000 model. Similarly, users can also create their own dataset of the catchment of interest to run the model.
Description of the test dataset
The test dataset of the Dudh Kosi river basin has been provided along with the tutorial. This dataset has been used for the PhD research and the publications can be download from here. The Department of Hydrology and Meteorology (DHM), Government of Nepal has provided permission to use the data along with the tutorial. The users are expected to use the data to get familar with different aspects of the J2000 modelling system. At the same time, they can also create their own dataset to analyse the hydrological dynamics of a catchment.
Motivation
This is the motivation of the study.
Study area
This is the Study area, Dudh Kosi river basin.
Objectives and methods
The main objectives of the
Preparation of dataset
Model parameter files
The requirement of the data to run the J2000 hydrological model is discussed in detail which is a pre-requisite to run the model. Two types of data are required i) model parameter files and ii) meteorological input data. The first one is prepared and quantified inside the GIS environment and known as model parameter files. The parameter files and their values are static in the modelling application. The detailed descriptions to derive the parameter files are provided below:
Soil parameter file
The detailed information required for the soil parameter file is provided in Table below.
| Parameter | Description |
|---|---|
| SID | soil type ID |
| depth | thickness of soil |
| kf_min | minimum permeability coefficient |
| depth_min | depth of the horizon above the horizon with the smallest permeability coefficient |
| kf_max | maximum permeability coefficient |
| cap_rise | Boolean variable, that allows (1) or restricts (0) capillary ascension |
| aircap | air capacity |
| fc_sum | useable field capacity |
| fc_1 ...22 | useable field capacity per decimeter of profile depth |
The soil parameter file is one of the important parameter files which needs a range of information to produce a comprehensive characterization regarding water holding capacity of different soil types. For this, the texture information of soil types of different soil horizons are required. A detailed description of how to produce soil parameter file is provided here: How to create soil parameter file
Land cover parameter file
The land-use parameter file requires information about the land-use and land-cover of a catchment. Such information can be derived from literature where the spatial information about the land-use and land-cover is provided. Alternatively, such information can be estimated using remote sensing images and subsequent classification. The J2000 hydrological model requires primary classification of land-use and land-cover which affects the hydrological dynamcis. The land-use classes with similar features can be merged together which behaves similarly to hydrological dynamics. The major classification are provided in Table below.
grassland== coniferous forest== decidious forest= mixed forest= agriculture land shurbland bareland/per.snow waterbodies rockyMountains glaciers 1 = urban, densely 2 = settlement, loosely meadows and pastures bogs and wetlands
In case of few classes are available in the data (such as Forest), the user has to provided only one class for forest.
The J2000 hydrological model requires many different information about each land-use and land-cover types as provided in Table xx. It is hard to get these information for ecological region. However, certain information are primarily similar every parts of the world. The parameter values which are different in different ecological zones (such as LAI in Table xx) has to be adjusted by users based on the climatic and ecological conditions of the study area. For example, the LAI value is different in tropical (India) and temperate (Germany) region. in Germany the value of LAI is low during winter season as most of the leaves fall due to low temperature. However, in the tropical reason, few leaves are left in trees during winter season. However, certain information such as root depth remains same for each vegetation type for different zones. Users are free to change these values based on direct field measurement or literature. The detailed information about the land-use parameters and the application in different modules are provided in Table below.
- landuse.par
| parameter | description |
|---|---|
| LID | land use ID |
| albedo | albedo in % |
| RSC0_1 | minimum surface resistance for water-saturated soil in January |
| ... | |
| RSC0_12 | minimum surface resistance for water-saturated soil in December |
| LAI_d1 | leaf area index (LAI) at the beginning of the vegetation period |
| ... | |
| LAI_d4 | leaf area index (LAI) at the end of the vegetation period |
| effHeight_d1 | effective vegetation height at the beginning of the vegetation period |
| ... | |
| effHeight_d4 | effective vegetation height at the end of the vegetation period |
| rootDepth | root depth |
| sealedGrade | sealed grade |
The relevancies of these variables in calculation of differnt water cycle components are provided in the following documents.
Krause 2001, Krause 2010, Nepal 2012
The land-use parameter file of two regions are provided herewith, as an example land-use parameter file (Thuringia region, Germany) land-use parameter file (Dudh Kosi, Nepal, Himalaya)
Users have to prepare the land-use file in raster format with certain resolution. The resolution depends upon a catchment to be modelled. If the catchment is small (600 km2), the resolution between 30-90 is suitable depending upon the resolution of the available dataset. Similarly, for meso-scale catchment (4000 km2), resolution between 250-500 m is suitable. The resolution of the dataset is important for deriving the number of HRUs.
Geological parameter file
xx
HRUs/Reach parameter file
Hydrological Response Units (HRUs) are the modelling modelling entities for the J2000 hydrological model. The processing of delineating HRUs are described in the following tutorial.
Meteorological input data
The J2000 hydrological model requires the input of the hydro-meteorological data as provided in Table below:
