Questions tagged [wind]

The flow of air with respect to the ground. On the surface of the Earth, wind consists of the bulk movement of air.

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7
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2answers
3k views

Where can I get archived hourly wind speed data for Germany?

Can some one suggest me a web site for archived hourly wind data for Germany. I have seen here but it was not useful for me.
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Plotting the wind direction in 3D?

How can I plot the wind direction in 3D, using the 3 wind vectors u, v and w? Normally, I ...
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937 views

How do weather services measure wind

I'm curious to know where commercial weather services like the Weather Channel and Weather Underground get their wind speed and direction measurements, to produce maps like this one (http://www....
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About an alternative type of wind energy facility

Many people seem to complain about large wind farms. Instead of all that, there are many cities with all their tall buildings that actually 'magnify' the wind or augment it. Even corridors through a ...
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1answer
110 views

The effect of buildings on frost

I have see this morning this curious garden where one part was covered with frost while the other was frost free. Question 1: What are the factor that play a role in this configuration? My guess ...
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How do I represent wind direction on a UTM (Universal Transverse Mercator) map projection?

What does it mean when I say "the wind direction is 50o" on a UTM map? Which direction is the 0o reference? For example, if I draw a wind vector V as seen in the ...
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1answer
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Plotting wind barbs in python

I'm trying to plot wind barbs in basemap and I have two separate netCDF files. Here is what I am trying to produce, or something like it: How do I read a uwnd variable in a netCDF file in python? <...
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How is there enough $\ce{O2}$ in the atmosphere to breathe if you are in a desert with no plants?

Humans depend on $\ce{O2}$ for breathing. The source of $\ce{O2}$ is photosynthesis by plants or cyanobacteria in the ocean. How is it, that when people travel through deserts or the Arctic / ...
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1answer
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Are oceans a major factor in creating high winds on a planet?

This question only pertains to oceans of water and how much they account for the process of creating high winds on a planet with any type of atmosphere.
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Would there still be wind if Earth had no water?

If there was no water on the earth would there still be wind? If the planet was basically a desert from pole to pole, east to west, would the wind still blow? I understand that wind is a result of a ...
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529 views

Website that contains the maps of atmospheric pressure and wind speeds

Is there a website that contains the maps of atmospheric pressure and wind speeds for specific climatic events such as hurricanes day after day ?
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Spatial variability in ocean surface winds

For the near-surface winds over the ocean, many model products and satellite footprints have spatial resolutions on the order of tens of kilometers. I'm interested in knowing how much the winds (both ...
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Is this ice cover real - and what circumstances are required to make it?

The title says it all... I assume it requires very slow freezing sheltered from the wind. Undercooled water, maybe? A Reddit thread talks about Delaunay triangulation, but that does not explain how ...
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Wind profile below the aerodynamic roughness length

The vertical profile of horizontal windspeed is often given by the so-called "log-law": $$u(z)=(u^*/k)\ln(z/z_0),\ \mathrm{for}\ z>z_0,$$ which can be found here. As can be seen from the ...
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Why do certain areas on Earth have a higher or lower air pressure at sea level?

For instance, looking at this map of world air pressure in January and this map of July, why do some land surfaces have a higher pressure during the winter? I know that the tropics and Coriolis ...
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Intuitive definition of the Monin-Obukhov length?

The Monin-Obukhov length (L) is defined as: $$L = - \frac{\rho C_p T_v u^3_*}{kgH}$$ where $\rho$=moist air density; $C_p$=air specific heat capacity; $T_v$=virtual temperature; $u^3_*$=wind ...
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Does "wind" include the air molecules involved, or merely the kinetic energy?

This question is about a riddle in which the statement "I am weightless" was made, and the answer was "wind". I want to know, by definition, does the wind include the air being moved, and thus have a ...
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What is the difference between roughness length and zero plane displacement?

Both roughness length $z_0$ and zero plane displacement $d$ seemed to be defined as the height above the ground at which wind speed theoretically becomes zero. But wind speed is also supposed to go to ...
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Does within-canopy wind direction correlate with wind above the planetary bounday layer?

Wind above the planetary boundary layer (PBL) tends to be fairly smooth and constant over short periods of time. Below the planetary boundary layer, the smoothness is broken by eddies caused by ...
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Why does the Inter tropical Convergence Zone shift?

I am currently learning at school about the climatic conditions (mainly winds, difference in pressure, Coriolis effect, etc.) that cause and affect the monsoons received by India. One of the factors ...
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Why is ocean surface velocity around 3% of wind velocity?

Many introductory level textbooks suggest that, as a rule of thumb, the velocity of the ocean surface is around 3% the wind velocity at 10 meters above the sea surface. For instance, Ocean ...
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Why does air seem to affect local surface temperatures so much?

Last winter, several areas in the US and Canada were hit by a "polar vortex." I happen to live in one of those areas and was amazed how much the temperature seemed to change so suddenly just because a ...
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How to determine that sustained wind speed exceeded the threshold value?

Certain maritime ports and airports have ranges of operation relation to the wind, usually according to a given threshold value of sustained wind speed. If I have the instantaneous values from ...
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Could the extraction of energy by wind turbines be harmful to the environment?

Wind turbines work by converting some of the energy from wind to electrical energy. Is it possible to have too many turbines, leading to them removing too much energy from the wind? I'm not an ...
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How can odor travel be tracked

Odd question, but what data would be needed to to calculate how far winds will carry a strong odor (such as the smells of a restaurant, pizza parlor or burning wood/building? There is wind direction ...
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Potential explanations of Red Sea crossing

I am looking for a believable explanation of the Red Sea Crossing in the Bible. This would involve either strong winds(which is mentioned in the Bible) or plate tectonics which could cause land to ...
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Why is aerodynamic resistance defined inversely?

When I think of wind resistance, I always think of the friction co-efficient, in $\mathrm{ms^{-1}}$, because that's always the way that it was presented in highschool and undergraduate physics. But ...
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781 views

Significant difference between averaged wind speeds and averaged wind power density, for wind generation modelling?

Climate models outputs, particularly the reanalysis datasets, output wind speeds as zonal and meridional averages for the modelled time period (typically 1, 3 or 6 hours). So we get a 2-dimensional ...
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293 views

Sea breeze - magnitude of horizontal pressure gradient?

What is the range of horizontal pressure gradients typically caused by the differential heating of land and water under sea breeze conditions?
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What exactly is wind velocity

How exactly do we define wind velocity? Obviously, I suppose this is something like "speed of displacement of a quantity of air", but this seems to be too imprecise. For example, a cup anemometer ...
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Why is there no middle ground between tornadoes and hurricanes?

A tornado has an effective area of destruction about the size of a city block. A hurricane spans several hundred kilometers. However, there doesn't seem to be a continuum between the two. Why are ...
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Is there a reliable way to identify regions with negatively-correlated winds?

When examining the potential for large-scale electricity grids, and when identifying the lowest-cost ways to generate clean electricity, a recurring theme is of spreading wind generation across a wide-...
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Winds in a northern hemisphere hurricane

In the Northern Hemisphere, do surface winds around the center of a hurricane move counterclockwise and inward or counterclockwise and outward? I'm guessing they move inward.
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Why does the wind periodically change direction?

Image Subtitle: Wind going across the page - and changing direction To clarify, imagine you were sat in a boat in the middle of a lake recording the wind direction every minute. You notice that the ...
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Is it possible for a sting jet to form over a continental landmass?

Sting jets are thought to be responsible for some of the most damaging winds associated with extratropical cyclones in the mid-latitudes. So far they have only been confirmed in the European region, ...
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Where does wind come from?

Wind is (according to Wikipedia) the flow of gases on a large scale.On the surface of the Earth, wind consists of the bulk movement of air. What forces would cause such a mass movement of air?
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What do quasi-geostrophic and ageostrophic mean?

I know that geostrophic flow means straight wind flow that is balanced by the pressure gradient and Coriolis forces. But what do quasi-geostrophic and ageostrophic mean specifically?

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