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12

The equal-area projection used to create the continental U.S. grid for weather forecasting does not represent lines of latitude and longitude as straight lines. Instead, they are curved (note the Canada-USA border curvature below, which is actually along the 49th latitude parallel). An equal-area projection is often used in regional weather modeling ...


10

Let's start by the quick rule of thumb, I'll follow the way I do it mentally as I think the mnemonics I use could help you too. First, the tropics are at 23.5° of latitude. And remembering that the original definition of meter is "A ten-millionth of an Earth's quadrant", it means the perimeter of Earth is 40,000 km, that consist on 360° of latitude, then: $...


8

Both the tropics of Capricorn and Cancer are 23.43692 degrees from the equator. So the angular distance between the two is 46.8738 degrees (2 x 23.437) of latitude. One nautical mile is defined as one minute of latitude. This is equivalent to one 1/60 of a degree. Thus, the distance between the tropics, along the surface of the earth is 60 x 46.8738 = ...


8

TLDR; The precipitation values (and possibly some other variables; see below) need to be divided by 24. Background The global attributes of the netCDF file in the question provide an URL to a description page: coastmod.hzg.de From that URL a user should be redirected to wiki.coast.hzg.de/display/MD (access at 9th Feb 2018). Unfortunately, the redirect ...


8

Yes. current climate change will most likely increase the amount of cultivable lands on Earth. However, it will at a high social cost and at the expense of biodiversity, and I can't emphasize enough the paramount importance of biodiversity for the heath of ecosystems and human food safety. Consider also that similarly to mining, where the value of a deposit ...


6

As Boston and Rhode Island are whole areas more than points, the question is easier to answer the other way around: From which mountain you can see Boston and Rhode Island? To answer the question I'll use the SRTM Digital Elevation Model at 30 meters resolution, and pick the following five mountains or hills that seem good candidates: Shown elevations are ...


3

Take a look at the RSAGA package on CRAN, or the rgdal package. Many of the GIS methods can be done in R but basically act as a wrapper for saga or gdal. RSAGA is likely your best bet for processing terrains for flow analysis. I also know of Dan Moore from UBC who does a lot of work with R and GIS applications, worth taking a look there and certainly those ...


3

The UTM coordinate system, is a kind of Transverse Mercator projection separated in longitude bands and restricted in latitud extent such that the distortions associated with the projection remain small. Also, the UTM coordinate system is conformal projection. Therefore, it preserves the angles. That means that within the UTM zones, a straight line in UTM ...


3

The latitude and longitude of each pixel is not stored in the HDF file. But using metadata=hdfinfo('file_name.hdf'); You can get the info to generate those latitudes and longitudes. In metadata.Attibutes you will find this among other things: GridName="MOD_CMG_Snow_5km" XDim=7200 YDim=3600 UpperLeftPointMtrs=(-180000000.000000,90000000....


2

That kind of "moving clouds animation" is a very common one, as it is used routinely to aid in weather forecasting. However, it is not very common to see it in a whole-world geographic projection as the example you show, I'll elaborate later on why that's the case. Traditionally, a common source of "cloud animations", have been NOAA's geostationary GOES ...


2

I think there are a few things to consider. First, a drainage basin is defined as the area upstream of the point to which all precipitation converges. Flow does not converge at the outlet - flow converges at the lake. Outlets don't contain any additional information of the upstream area draining into the lake. This implies that to find the area draining into ...


2

The problem (if there is only one) is in the way you are importing the data into .mat file. If with the files you provided I do data = load('sc_8days.mat') ; data = data.sc8days ; [nx,ny,d] = size(data) ; imagesc(data(:,:,1)); I get this nonsense: and d=23, while the MOD10C2 data has only four bands: Eight_Day_CMG_Snow_Cover, Eight_Day_CMG_Cloud_Obscured, ...


2

Google Earth Engine's NASA NEX dataset (or this) might be of interest to you. It is an online repository, where you can do your analysis using the GEE platform without having the need to download to local machine.


1

I would recommend looking at automatic stream network delineation and/or known stream locations features, and overlaying those as a check on the final watersheds created through whatever procedure you have. Watersheds can be merged or lumped together, which is fine, you just want to make sure it is consistent with the other information you have and what your ...


1

I'm confused about your misunderstanding as the answer to your question is in the Wikipedia link you posted: Regions receive a two-digit code. The following levels are designated by the addition of another two digits.[8] The hierarchy was designed and the units subdivided so that almost all the subbasins (formerly called cataloging units) are larger ...


1

Exciting question... it's something I've wondered as well, both for interest purposes and for utility in programs like you mention (I posed a fairly related question in the cartography SE site proposal). I've searched a long time but could not find any term/calculation for this... perhaps I too just did not know the correct term to use? As a result, for a ...


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