50
votes
Accepted
What is the line crossing the Pacific Ocean that is shown on maps?
It's the international date line and marks the boundary between the time zones that are +12 and -12 hours from UTC / Greenwich. It should follow the +/-180 degree meridian line, but zigs and zags to ...
- 735
42
votes
Accepted
Where on Earth is the magnetic field intensity stronger?
If we consider only the magnetic field generated by natural sources, and not the ones generated by human activities. The general trend is that higher intensities of the magnetic field happen close to ...
- 17.7k
39
votes
What is the line crossing the Pacific Ocean that is shown on maps?
Mkennedy's answer is right at identifying that line as the international date line and explaining how it works. However, I'd like to add on the main weird points of the line. North to south:
In the ...
- 829
22
votes
Accepted
Can living where (rare) earth magnetic ore is abundant provide any protection from cosmic radiation?
Absolutely not.
First of all, "rare earth magnet ore", meaning the ores of metals like neodymium (Nd) and samarium (Sm), is not magnetic at all. It only becomes a magnet once you make a ...
- 23.1k
18
votes
Accepted
Are there seamounts as close as 100 m to the water surface and not inside any Exclusive Economic Zone?
Yes, there are many. According to the seafloor topographic data of ETOPO (1 arc second resolution), and the Exclusive Economic Zones (EEZ) database of marineregions.org. There are at least 157 ...
- 17.7k
13
votes
Are there seamounts as close as 100 m to the water surface and not inside any Exclusive Economic Zone?
Checking the Wikipedia page on underwater volcanoes and listing them by height, I think the best candidate is Vema Seamount. Vema Seamount is in international waters and its shallowest point is at 11 ...
- 15.4k
13
votes
Where on Earth is the magnetic field intensity stronger?
Since it is not specified in the question (and to complement the other answer), the strongest magnetic fields on Earth are not naturally generated, but artificially.
The current world record holder ...
- 331
12
votes
Accepted
Where on Earth has the least changing temperature?
To answer the first question, yes, there are maps showing the seasonal temperature variation, for example here
Unsurprisingly, the equatorial areas have the least variation because the angle of the ...
- 851
11
votes
Accepted
At what depth does the underground begin to warm up?
Your question has an incorrect assumption built in. Near surface ground water temperatures are not generally colder, but rather reflect the average annual temperature. This will be colder than ...
11
votes
Can living where (rare) earth magnetic ore is abundant provide any protection from cosmic radiation?
No.
Cosmic radiation are high-energy particles that create particle showers high up in the terrestrial atmosphere. Those particle shower are heavily beamed downwards, and although in principle some ...
- 3,172
10
votes
Accepted
What is the chasm in the Arctic on Google satellite map?
You probably realise this, but you're not seeing that directly from satellite photos. Google Earth (or the "satellite" view in Google Maps) shows direct imagery on land, but underwater it shows a ...
- 5,810
8
votes
What is the average color of soil?
Soil color is largely determined by it's composition.
There are three main components in soil:
Gravel, sand, and silt. In essence, the type of stuff you find in sedimentary rocks. Usually, this is ...
8
votes
Accepted
How much of Earth's land area has antipodal land area?
A rough idea, using the Lambert Conformal image at the Cartopy projection list and Gimp:
The gold area should be the overlap. So basically parts of South America with Indonesia and SE Asia... and ...
- 8,822
8
votes
A circle shape in Madagascar
It is an extinct volcanic crater.
The location is not listed as one of the active volcanoes in Madagascar.
Simplified geologic map of Madagascar (reference) shows the crater to be mapped as basaltic /...
- 5,959
8
votes
Accepted
What kind of projection is that?
It looks to me like a sinusoidal projection centred on -30°W, with edges at -90°W and 30°E. For that projection, the length of the parallels goes as cos(latitude), so we expect the ratio of the widths ...
- 1,047
7
votes
Accepted
Street and road data
Google Maps and MapQuest have gathered data and information through subcontractors and their own internal efforts. Their information is proprietary and is very hard to gain access to (and most methods ...
- 572
7
votes
Accepted
Old topographic maps of Odisha, India
The PCL Map Collection (University of Texas at Austin) is a huge online collection of maps. For India, they have a series from the U.S. Army Map Service which might be of interest, as it dates from ...
- 8,141
7
votes
Accepted
Geotiff for Elevation Data or NetCDF
'Better' will depend on your planned usage - any global product will have limitations in terms of overall accuracy and precision, and both the Aster photogrammetric data and the widely used radar SRTM ...
- 2,090
6
votes
Accepted
How to Interpret this set of Latitude and Longitude?
It looks like your coordinates are written in decimal degrees but with the decimal points omitted.
34.144442 -118.654084 corresponds to 34°08'40.0"N 118°39'14.7"W.
Google maps shows this to be a ...
- 2,201
6
votes
Accepted
What are the best maps, if any, we have of the convection cells in the Earth's mantle?
If you're looking for a cool, well detailed map of convection cells that looks like a modern weather map....forget it. What you're looking for has been notoriously difficult to produce, if not ...
- 2,813
6
votes
Accepted
In Geology - True Dip versus Apparent Dip: When dip is estimated along a line of section, how is that dip determined in relation to true dip?
This is an excellent question. The answer requires that one visualize a 3-dimensional space with a dip plane, a vertical plane coincident with, and aligned along, our line of interest, and the trace ...
- 76
6
votes
Accuracy of continental drift maps?
"Very obvious" is wrong.
You have to look at more than just the rough shape of the land surface, first continetal crust often extends below the water line. Then you need to look at the ...
- 7,026
5
votes
At what depth does the underground begin to warm up?
The temperature would stabilize to a steady temperature when you go down 15 ft or so. The point where it gets significantly warmer is probably much deeper than you want to go.
A better system ...
- 51
5
votes
Accepted
What are these radial line patterns shown in representations of antarctica?
I can't be sure, but I strongly suspect that the radial lines in the first two images are the result of a bug in the software used to draw the map, probably resulting from vector polygons that are ...
- 5,810
5
votes
Realtime planetary gravity maps?
For sure this is not available.
To create those maps takes several dozens Earth orbits by GOCE (one orbit ~90 minutes) and possibly many more to bring up the signal to noise
Which gravitational ...
- 3,172
4
votes
Accepted
Where on Earth is the highest none polar magnetic fields?
In other words where might be a natural place on Earth that would over power a compass and then some
Just about anywhere where the rocks are rich in iron. This would occur near iron ore, basalt, ...
- 23.1k
4
votes
Accepted
Software for spatial interpolation of temperature and relative humidity data from weather stations
I am presently working on exactly this.
I am using climate reanalysis data, to fill in the 'empties' since my climate stations are far away from each other. Or, sometime, I have N/A's in my series ...
- 2,669
4
votes
Where can I find geological maps for countries from Africa?
You may find some of the maps you seek on the OneGeology portal, which gives access to both regional mapping and maps uploaded by national geological surveys. You could also review the data available ...
- 2,090
Only top scored, non community-wiki answers of a minimum length are eligible