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16

Mountain ranges are usually formed as orogeny where tectonic plates collides, known as convergent boundaries. The continental plates have less density than the oceanic plates and the buoyancy results in that they are mostly above sea level. Continental sea floor is known as continental shelf, but usually, it doesn't reach far from the coastline. Therefor ...


14

First off, your observation that Tamil Nadu gets more rainfall in the evening is partially backed by records. Sahany, Venugopal, and Nanjundiah, 2010 provide data on diurnal scale rainfall distribution during the Southwest monsoon season shows that Tamil Nadu is dry from 0530-1430 each day, and likely to be wet from 1730-0230: The Northeast monsoon is ...


12

Almost all finite methods that use forward time models adhere to the Courant-Friedrichs-Lewy law which calculates a courant number and compares it to a $C_{max}$, which is what determines stability, so for 2-D: $$C = \frac {V_xdt}{dx} + \frac{V_ydt}{dy} \ge C_{max}$$ Where $C$ is the courant number, $V_i$ is the velocity in subscripted direction, $dx$ or $...


11

Short version; the beach moves because the waves change. Long version; Beaches, and in fact entire bays, conform in shape and alignment to the prevailing wave patterns in the area. The exact magnitude and alignment of wave trains varies due to chaotically complex interactions between surface winds, subsurface currents, local seabed features, tide, larger ...


10

The usual panacea for numeric stability problems is to decrease the timestep. It doesn't always help (and, indeed, in some cases can even make the instability worse), but it's generally the first thing to try. Of course, a shorter timestep costs more computer time. Another approach to try, if reducing the timestep doesn't help, or leads to unacceptably ...


7

The amount of sand on the beach at any one time is a dynamic quasi-equilibrium between a whole raft of processes. These include wave power, frequency and direction, seabed angle, longshore drift, rips and undertow, wind strength, direction and continuity, fetch, coastal geomorphology, sediment availability, offshore currents, and probably other variables. ...


6

If you see the other user (Jan Doggen's) google maps link, you can see apparently similar features in different states - this is a particularly neat example of a general phenomenon. These notches form when headlands are undercut by caves carved out by the sea. They may be initiated where there is a fault or jointing in the rock (northwest Jersey is granite, ...


6

These are actually a geological feature called "fjord" which the Scandinavian Peninsula and surroundings (including Scotland) are known for. It is the result of glacial erosion during the Ice Ages. See more info here: Fjord (Wikipedia).


5

There's a huge literature on this problem, and depending on who you ask you will get different answers. I'll come at it from the geomorphology perspective. The most uninformative explanation is that sand moves around by the action of water or air. But, how it does so is dependent upon the beach feature/aspect you're trying to describe. Air moves individual ...


5

The Northwest of Scotland has a common linkage to Norway in that both are the remains of the once-mightly Caledonide chain of mountains. This was before the Atlantic Ocean opened up, so other fragments of the Caledonides are to be found in Greenland and Eastern North America. See for example the diagrams found in Haakon's website: http://folk.uib.no/nglhe/...


4

Why are waves from full width oceans critical for the formation of cliffs? There are many cliffs in inland regions, particularly, mountainous regions & escarpments along rivers. The sides of Table Mountain in South Africa appear very much like a cliff, as do the sides of mesas. Escarpment cliffs usually occur along geological faults. Some of the largest ...


4

There has been lots of works trying to reconstruct the evolution of the Gulf shoreline through time. They do not agree on the exact same dates (see this review by Sissakian et al. 2020), but they generally agree that there was first a transgression (sea level rise) episode following the last ice age, then a regression (sea level drop). Reasons invoked to ...


3

Wikipedia does not include Alert as a port. As the comments suggest, there is too much sea ice at that latitude to merit the infrastructure required of a port. The northernmost port in the world is identified here as Dikson, Russia, at 73°30' N. Supplies to Alert are delivered by air; the settlement does include an air port.


3

It should be noted that NetCDF data just describes the format that the data is in. One dataset that I know of (IBTrACS) contains data that is not gridded data, and also contains a landmask. But this is besides your question. To rephrase your question: How can I determine the orientation of the coastline in a gridded dataset? Well, one way is using ...


3

It is called Companion planting, and it is actually fairly common with hand tended fields. It does not work well with mechanized agriculture which is why you don't see it much in large scale farming. It is however, fairly common in gardens and non-industrial farming because they do work well. It has a variety of benefits depending on what exactly you are ...


3

With desalination plants the import thing to consider is from where such plants are taking water and where they are disposing of their waste. The waste from desalination plants is either salt of very salty water. If the plant you are referring to is just dumping its waste on the ground nearby or into a nearby river or water channel it is possible that the ...


3

Not all coastlines have beaches. Some have cliffs, such the Great Australian Bight, which forms a significant part of the southern coast of Australia. The limestone cliff portion of the Bight is over 1000 km in length and between 60 and 120 metres in height. Similarly, in the Otway region of the Australian state of Victoria forested hills form the coast in ...


2

There are public databases with the coastline in lon,lat format. You just need to find the point closest to your coordinates in that coastline. For that you need the formula of the distance between two lon,lat points on an ellipsoid. In this article you can find that and an idea of how to do it: Garcia-Castellanos, D., & U. Lombardo, 2007. Poles of ...


2

There were certainly river mouths or estuaries in the rivers that drained off the proto-Himalayas into the last retreating stages of the Neo-Tethys Ocean. Such rivers comprised dozens of small rivers and the westward-flowing Proto-Ganges itself, which deposited the Siwalik formation which now forms the Lesser Himalayas. That is, the southernmost 'soft' 'salt ...


2

Your question is actually a three-part question in disguise, of which I cannot answer all parts, but let me tell you what I do know. Part 1: What causes variations in vertical position within the context of the refered sentence? If you read that section more carefully it is not so much variation of the seabed depth, but variation in the measurement of the ...


2

I also live on the coast and have been concerned about what to expect with regard to sea level rise in the near future. The following graph illustrates the observed rise in sea level over the last 30 years: As you can see from the image, satellite data indicates a linear increase in sea level rise of 3.3 mm per year for the last 30 years. If this trend ...


2

At the coast the horizon facing the ocean is unobstructed, so a larger part of the sky is visible than inland, where trees, buildings, etc., block the view of the horizon. Also, the horizon sky is brighter than the overhead sky. At or near the horizon the sky appears lighter blue than at the zenith, or even whitish. Looking vertically at the zenith is ...


2

Well, let's start with a rough global map (from NCEP Reanalysis) of the average winds speeds (in meters per second): Multiply by 3.6 to get km/hr. So your range is basically from 3 m/s to 4 m/s. So you're looking at the medium blue color basically. There are some coastal locations. But generally, coastal locations will have quite a bit of wind... What ...


1

Taking water out of the sea does require energy to lift it even if it's destination will eventually be below sea level. The dam idea of retaining rain water would require energy and resources for the production of the dam and require the loss of usable land. That is not the best dam way to approach this solution. Removing water up stream, from say the ...


1

This is no an answer per se, just a back-of-the-envelope calculation for fun. Lifting 1 kg (one litre) of water up a height of 1 meter uses 9.8 (let's say 10) joules of energy. Let's say you want to lower the sea level by 1 meter. You need to pump 3.6e17 litres (3.6e14 m2 of ocean area = 3.6e14 m3 to pump * 1000 for litre conversion). Let's say you want ...


1

I would recommend changing from ERA-Interim to ERA-5, since ERA-Interim will be outdated soon. This is the information currently given by the data provider: ERA Interim is being phased out. Users are strongly advised to migrate to ERA5. The last date to be made available in ERA Interim will be 31 August 2019, which will be released at the end of October ...


1

Some desal plants takes brackish water from under ground and treat it. YES it does cause problems with salinity, though the water used is often pumped back underground to be used again. But desalination plants that take water from the sea have no effect on ground water, if anything they can be used to regenerate ground water by agreeing to donate certain ...


1

Venice has plans for a new hydraulic flow controlled by levees and a dam during runoff & tidal events as sealevel continues to rise. This has a brief summary of progress: https://www.citylab.com/life/2016/09/venices-vast-new-flood-barrier-is-almost-here/498935/ [edit] The context of Venice has 3 parts, the freshwater seasonal and episodic flow ...


1

Sorry to be un-arty but you should be able to measure scattered light intensity at the coast versus inland. My guess is that it is brighter at the coast which also probably also means it gets lighter in the morning and light lasts longer into the evening. Land in the place I live is covered in green and is quite absorbent of light, i.e. dark. It's pretty, ...


1

Could be formed by two natural processes. First, some fault with shear zone, which is obviously much weaker than the rock around it and gots weathered faster. Second, could be some vein/dyke of some mineral or rock softer than surrounding rocks.


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