A message from our CEO about the future of Stack Overflow and Stack Exchange. Read now.
50

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 include territories or islands within a "day" thus the Aleutians islands are in the same time zone as the Hawaiian islands.


39

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 Bering sea, the line bends eastward to include all Russia in the same side, and then it bends westward to include the Aleutian islands on the same side as Alaska ...


31

Oasis are places where aquifers are connected to the surface. The source of the water in the aquifer however can be hundreds of miles away in areas that do get significant rainfall. The trick is geologic strat have different properties; some allow water to flow easily, others are very water tight, a water accessible layer covered by a water proof layer ...


15

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 seafloor features higher than -100 m (closer than 100 m to the sea surface). With that data, I made the following figure that shows: ETOPO topographic data All EEZ ...


14

There are two types of oases: natural and human made. Natural oases form when springs, created when underground aquifers allow fresh water to pool or flow on the ground surface of deserts, creating a fertile region. A human made oasis occurs when humans create fertile region in a dry or arid region, such as a desert. The supply of water in human made oases ...


13

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 meters from the surface. It is so shallow that it represents a navigation hazard.


10

I wrote a little Matlab script to estimate this approximatively. Here is the result: colour denotes the total land area inside the hemisphere centred on a particular surface point. The red point is the maximum. This gives me a maximum for the hemisphere centred on 1.7582°W longitude and 40.7692°N latitude, roughly in Guadalajara, Spain. If I calculated ...


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 ...


8

I would assume that's the highest point on the equator you talking about, so The highest point on the Equator is at the elevation of 4,690 metres (15,387 ft), at 0°0′0″N 77°59′31″W, found on the southern slopes of Volcán Cayambe [summit 5,790 metres (18,996 ft)] in Ecuador. This is slightly above the snow line and is the only place on the Equator where snow ...


7

Lake breezes(similar to sea breezes) are fundamentally a feature of mesoscale meteorology and the peer reviewed reference Small Lake Daytime Breezes: Some Observational and Conceptual Evaluations details both the observational studies of lake breezes and the conceptual understanding behind the formation of the lake breeze. Since OP's question is How big ...


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 ...


5

The original wording of your question revealed that you are missing something about what time zones are, and how they are defined. So let me start from the begin. If you are impatient, you can jump forward for the answer in bold font after the figure, and come back here for the explanation. Time zones are defined by by man just to facilitate time keeping. ...


5

The total land area of earth is approximately 29%. So, in order to have a hemisphere with more land than water, out of 29% of total land area we need to have at least 25% of it concentrated in that hemisphere. Now for the ease of understanding, what does 25/29 of total land area means? It approximates to 86% of the total continental surface area. Area of ...


4

As @gerrit commented, a precise calculation would need to incorporate a litospheric model to account for isostatic post-glacial rebound. But the "blurry approximation" you want, can be obtained based only on topographic data. This approximation would be reasonably accurate if the melting of the ice happens quickly. For this, we need topographic data of the ...


4

Considering it's now my profession as a geomatics technician, I don't really need a mnemonic technique to remember which is which, but when I first had to remember the orientation of latitude and longitude, I simply did this: Consider the equator as the horizon and switch two letters in latitude so it becomes altitude. There you go, latitude is the (...


4

First let's define the terms: Peninsula: A headland or promontory surrounded by water but connected to the mainland by a neck or isthmus. Source. This definition is similar to the aforementioned and provide a few examples, underlining that the size (scale) is not an important criteria characterizing peninsulas. For example Baja California (Mexico) is ...


4

Australia does get widely referred to as an island as well as as a continent - an island-continent sometimes. My understanding is that "continent" in terms of geology refers to the largest land mass of a continental plate and is more a matter of convention - a general agreement - than precise definition. Such definitions have been subject to revision. This ...


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

Since OP wants data in text format to plot pressure, temperature and dew point data this site University of Wyoming soundings map does provide data in a text format as shown in this example for Essen Germany.


3

$\text{Poulation density} = \frac{\text{Population}}{\text{Surface}}$ Re-arranging $\text{Surface} = \frac{\text{Population}}{\text{Poulation density}}$ In your case $\text{Surface} = \frac{100,000,000\, \text{inhabitants}}{10\, \text{inhabitants}\, \text{km}^{-2}}=10,000,000\, \text{km}^2$ So something doesn't make sense, because those numbers ...


3

There are a couple of possibilities, depending on what you're paying the most attention to. This falls in an overlap area of terms that vary from region to region and even from person to person. The key thing to notice in your photo is the whitish band running along the top of the escarpment that borders your landform. This shows that it's held up by a ...


3

There is a similar and bigger chalk plateau at "plateau d'urle" in France. That one looks like a "chalk plateau of continental shelf origin with straight channels eroded into the underlying clays", by it's flatness and proximity to the sea. The geologists write that the chalk is a freshwater lake chalk deposit due to it's fossils. The sediments are layed ...


3

The visibility or "clearness" is more a matter of suspended particulates, and organic material such as algae, than of dissolved material. For instance, runoff from glacial streams can be nearly opaque due to suspended rock flour, yet "pure" in the common sense of not having much in the way of algae &c. Conversely, some parts of the oceans can be very ...


3

Depends on the context. Examples can be: In depressions instead of lonely on the plain, inside of the forest instead of at the edge, along a river bank or lakeside instead of on dry ground. Or, in short: exposed to wind & weather instead of sheltered from the rigour. Also depends on the tree. Some pioneer trees can grow individually in adverse ...


3

It's basically a (rough) description of the relative wind speed on the site compared to the local average. If a site is sheltered, it will typically experience: lower wind speeds, potentially warmer mean temperatures, and (in temperate zones) a lower risk of frost (although some sites may actually have an increase due to catabatic airflow: "frost hollows") ...


2

Easiest method I use is "Lat(itude) = Fat(itude)", imagining left-to-right lines of latitude looking like a fat belly (or belt) protruding over a tight belt. That does the trick, but as a secondary mnemonic, I then imagine "Long" as a measure of tall/lankiness, as I'd never describe fatness/width as "long".


2

Found in https://twitter.com/amazingmap I can't personally vouch for accuracy. From tweet, several complaints about Antarctica, "wrong pole", etc. New favourite map projection. Hellereal Boreal Triaxial Projection From tweet World Mercator map projection with true country size and shape added #Map #Maps #Amazingmap #Amazingmaps #Mercator


2

ARID LANDS: CHALLENGES AND HOPES by EARTH SYSTEM: HISTORY AND NATURAL VARIABILITY – Vol. III - Arid Lands: Challenges and Hopes - Barakat H.N. Hyperarid zones cover 7.5% of Earth's land surface, arid zones cover 12.1%, while semiarid zones are more extensive, occur in all continents, and cover 17.7% of Earth's land surface. The dry subhumid category ...


2

There are some wonderful answers here, but I think a simplified plain English answer would be helpful. Barring any nearby mountains, and various foibles, the closest point to the sun at the June solstice is where it is midday on the tropic of Cancer. At the December solstice, it is where it is midday on the tropic of Capricorn. At equinox it is where it is ...


2

After investigating a number of the options and data outlined I thought the STRM was the best bet. I was unable to find a place where I could download the data in a file that I could read into some software I'm familiar with the DEM file was in a binary format which I struggled with to ready into R so I started to work with the JPGs to read these in as ...


Only top voted, non community-wiki answers of a minimum length are eligible