A Tour of Climate And Hydrology Projections Archive Site

Hi, my name is Subhrendu Gangopadhyay. I'm a hydrologic engineer at the Bureau of Reclamation's technical service center in Denver. In this video we'll step through the process of retrieving climate and hydrology projections data for impacts analysis using the Downscaled Climate and Hydrologic Projections website. This site is a result of collaboration between several federal and non-federal partners. In a previous video I talked about necessary background information for using this site effectively. Now I'm going to give you a tour of the site and how to put together a data request. Before getting into any of the site's detail Please note the browser recommendations. Let's start with the Welcome tab. Here we have a summary, purpose and history of the archive. Check here for which data sets are currently available. Here on the About tab, we provide information archive development drivers and motivation, scope of the archive contents and projection attributes. We recommend you check this area periodically for information on updates and changes to the site. Here on the Climate sub-tab we have a list of the attributes available for each downscaling approach. These include variables, time and space. Note the different coverage and scope available for each of these approaches. The documentation and notes here provide some background on the currently available projections. On the Hydrology sub-tab we have a description of the attributes and approaches used for developing hydrology projections from climate projections. Here we describe the modeling scope and domain of the available downscaled projections. Here, we outline the available attributes to be chosen for each downscaling approach. On the Tutorials tab we provide examples of how to use projection output from the site in actual analysis. These tutorials are organized by downscaling approach, and provide examples of data retrieval and use of that data in impacts assessment. Next we are moving into the substantive area of the projections site, the Projections: Subset Request tab. This is the key area of the site you will use to get projection data. There are ten steps for getting projection data. These must all be completed before submitting the request. The Form Status boxes help track the steps. As they are completed, each one will be highlighted. When you have completed the 10 steps you will click the Submit Request button here. Here on the right we have an indicator of the file size of the data request. Three factors determine the size of the data request. One, the number of variables selected, two, the time period and three the spatial extent. If the size of the request exceeds 100 percent then you will not be able to submit the request. On the Page 1 sub-tab we will set the temporal and spatial extent. Here we will complete steps one through three, time step and period ... domain and spatial extent. You can choose either climate or hydrology projections or a combination of the two. I'm going to show an example using the Upper Colorado River Basin. Now for the first step, labeled 1.1, we look at time step and period. I'm going to choose the monthly time step for January 1950 through December 2099. For step two, labeled 1.2, I'll choose the Colorado basin for the domain. In step 3, for the spatial extent I'm going to use the tributary area for the Upper Colorado River Basin defined by this latitude and longitude which I'll paste here. This is the location of the Lee's Ferry gauge. When I click map outlet location this area appears on the map. Clicking on the location marker shows me tributary information. Also note that there is help available for each step by clicking on the question mark button. Up here in the form status area, we now see that we have completed the first three steps. Note the next step is labeled 2.4 which indicates page 2, step 4. Moving along to page 2 will select we'll select our projection sets. Here we see that because we selected monthly time steps, only the monthly projections are available. Let's select the BCSD-CMIP3-Hydrology- monthly projection set here in step 4. Now the corresponding sub-tab becomes available. On this tab for step 5, we will select our variables. Let's select Precipitation and Total runoff. In step 6 we will choose projections. Note, a projection is a combination of emissions pathway or scenario, climate model, and a run with a given set of initial conditions. The emission scenarios are in the three main columns. Each row represents a climate model. For each climate model and each emissions path there are one or more climate model runs represented by the checkboxes. Boxes that are grayed out represent unavailable runs. The buttons along the top allow selecting or deselecting all projections from each emissions path. So, now we see on our Form Status, that we have competed steps 1 through 6. On page 3, starting with Step 7 we are going to choose an analysis for the projection data or to simply extract the projection time series. We will choose Statistics and Spatial Mean. Certain statistics may not be available, depending on what variables you have selected. In step 8, we choose the output format for our results. NetCDF is useful for advanced users. We will choose ASCII text output. In step 9, we provide our email address to receive a notification and link to download the requested data. Finally In step 10 we ask that you provide some information on how you will make use up that data requested. This helps us track how well we are serving the needs of our various communities. Before submitting, check the form status to see if you have chosen all required variables. you can return to each step by clicking on the form status boxes. We recommend taking a moment to verify your selections before submitting your request. When you click Submit you will see as summary and another submit button to click after verifying your choices. The request is not submitted until you click the second submit button. After submission, a message will appear with an estimated time for completion. Looking up at the top level tabs, the Projections: Complete Archives tab provides FTP access to download any of the projection-specific full coverage data sets available for you to work with directly. Archives are posted in NetCDF format. Accessing the data archives in this way is recommended for advanced users only. Use the form on the Feedback tab to send us any questions or comments. Check the FAQ first to see if an answer to your question has already been posted. The Links tab provides additional resources and background information. The climate and hydrology model resources on this site will be updated, so be sure to check back periodically. Thanks for watching.