Questions tagged [meteorology]
The study of how the earth's atmosphere works, including weather forecasting. Use this tag for questions about the earth's weather. When asking questions specifically about the atmosphere, also include the [atmosphere] tag.
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Can firecrackers be used to subside thunderstorms due to cumulonimbus clouds
Cumulonimbus clouds are associated with thunderstorms. Firecrackers which go up high in the sky and then burst into glittering show, can such crackers be injected in a cumulonimbus cloud and then ...
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Why are eastern Oregon and southeastern Washington so dry?
Why are eastern Oregon, southeastern Washington and southern Idaho so arid, as compared to the humid and lush western Oregon and Washington? In Oregon and Washington there is quite an abrupt boundary ...
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Why was the flooding in Derna, Libya so catastrophic?
I have watched storm Daniel on the internet while it was in Greece and what I saw was much heavier rain than what came down in Libya. But in Libya, property damage and death toll were much heavier, ...
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Mass weighted vertical average of stream function in python
I have a netCDF file of stream function (psi) having dimension (latitude, level), level is pressure level. There are 5 pressure levels (700,600,500,400,300 hPa). I need to compute the mass weighted ...
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Dew-point temperature and absolute humidity
I am looking for a reference (e.g. book, peer-reviewed paper) that asserts that
absolute humidity is "equivalent" to the dew-point temperature.
Such statement should be true, AFAIU. Online, ...
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Why do tropical areas have low air pressure?
From the question Why are pressure levels raised on warm days?, my understanding is that the air pressure at surface level is not affected by temperature, as the mass of the imagined air column stays ...
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How to explain "Vacuum Cleaner Effect" for upper level PV anomaly?
In Jonathan Martin's Book "Mid-Latitude Atmospheric Dynamics" there is a chapter dedicated to anomalies of potential vorticity (PV). The scenario shown in the image below depicts a situation,...
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How to use 1D function metpy.parcel_profile in ERA5 xarray dataset open with dask
I really need help, I'm working on ERA5 hourly data on pressure levels. I've extracted relative humidity and temperature on several atmospheric pressure levels. I use Metpy's '...
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Why air laterally diverges before entering a cyclone/anticyclone?
I'm a newbie in meteorology so sorry if this is a dumb question.
I get the general idea of how cyclones form, but one thing I can't wrap my head around is why must the air diverge laterally when ...
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What is the highest evaporation rate in the world? I know evaporation rates for Australia
I have been searching for the above answer for more than 25 years.
I am providing a map of Australia for comparison
http://www.bom.gov.au/climate/maps/averages/evaporation/
Is evaporation rate 4000 ...
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How to use CMIP6 to predict windspeed in the future?
I'm very new to climate modelling and forecasting, I have chosen a project to forecast wind energy output in the future using wind speed prediction, I wish to use CMIP6 to predict. But I have very ...
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How is this global temperature chart compiled?
In this BBC News article, there is a chart labelled "Hottest day on record globally - Daily average air temperature, 1940-2023". It shows temperatures that are higher in summer and lower in ...
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Radially symmetric rainfall radar pattern?
I notice this radially symmetric weather radar pattern over London, UK today.
Is this a real weather pattern, or a measurement or model artefact? If it is a real weather pattern, what causes it?
The ...
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Will the hot Atlantic shape global/local weather and if so, how?
So the Atlantic Ocean exhibits record-breaking temperatures currently with about 1 degree Celsius above-average mean surface temperatures. This article, for example, mentions that a more severe ...
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Visualization of formation of cirrus vertebratus?
I am trying to understand how Cirrus Vertebratus are formed.
My book and many web pages simply say "waves orthogonally to the initial cloud formation direction, in fitting conditions, forming ...
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Weather record last month in the UK
On 22 June 2023 in my village in LE8, south Leicester, UK, there was a large deluge of rain and my house got lightly flooded - the only time ever in 30 years. I'm trying to make a claim now; the ...
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Why positive PV Anomaly moves westwards?
In Jonathan Martin's Book "Mid-Latitude Atmospheric Dynamics" there is a chapter about PV anomalies. As an example, a positive PV anomaly is discussed.
What is the reason, that high PV is ...
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Accurate Rainfall with TBRG
For an accurate flood forecast, up to what height maximum from the ground level one can put the TBRG without any obstacles and still receive accurate rainfall?
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What is the deeper difference between QG Omega equation and QG Height tendency equation?
The quasi-geostrophic $\omega$-Equation
is a diagnostic equation for $\omega$ (=dp/dt = vertical motion) in terms of geopotential. It is derived in a few steps by manipulating vorticity and ...
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Comparing expressions for Ertel Potential Vorticity and Quasi Geostrophic Potential Vorticity
In Meteorology there is a quantity called "Ertel Potential Vorticity" $q_e$ which is conserved considering isentropic flow ($\theta=const)$:
$$\frac{d}{dt}\left(\frac{1}{\rho} \vec \eta \...
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Why isn't Summer Solstice plus and minus 90 days the hottest in Northern Hemisphere?
If Summer Solstice around June 21 every year is the longest day of the year and closest to the sun for the Northern Hemisphere (maybe I should say receive the most direct facing sunlight), then why ...
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Linear and non linear relationship in MET office data - A-level maths
I am looking for relationships between different variables in a set of MET office data. The data set is for the months May to October in 2015 and 1987 in various places in the UK. The variables ...
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Is there a relationship between wind direction and the bearing of travel?
We want to move from point A to point B using a balloon.
If one knows the wind directions, How can one determine the altitude that will steer the Balloon to the desired location?
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Setting specific humidity vertical profile in an LES
I am working with an LES (Large-Eddy Simulation) model, and I want to define the vertical profile of specific humidity (qt) based on a given temperature profile (thl). However, I am not sure how to ...
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Why is one term missing in the derivation of continuity equation in isentropic coordinates?
In the book by Jonathan E. Martin "Mid-Latitude Atmospheric Dynamics - A First Course"
the continuity equation for isentropic coordinates is derived by applying conservation of mass:
$\...
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Unable to plot wind barbs of scatsat data in a ordered way
I have plotted wind speed and wind direction of scatsat data but wind barbs representing wind direction are plotted random (not in ordered manner.How to rectify this problem?
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How to download atmospheric/oceanographic data for a given region in the sea?
I am trying to get data of atmospheric temperature, wind intensity and/or atmospheric pressure for a specific region of the sea, since I have ocean bottom pressure data from a fixed instrument (lat,...
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Historic weather station data with hourly temporal resolution
I'm working with ERA5 weather data and am trying to understand some wind & temperature patterns that I'm seeing in my statistics. In order to do that I'd like to compare with some point ...
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Why is mixing ratio at LCL not the same as for starting condition?
I asked a question regarding mixing ratio and wet adiabatic lifting in
https://stackoverflow.com/questions/76244447/why-is-mixing-ratio-at-lcl-not-the-same-as-for-starting-condition.
I don't want to ...
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Estimation of extraterrestrial radiation for latitudes > 66.5° N/S
I'm posting here for the first time, so I hope not to violate any community-specific rules.
In Allen et al. (1998): FAO-56 an equation is presented to estimate extraterrestrial radiation Ra for ...
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Is equivalent potential temperature constant also for dry adiabatic processes?
Equivalent Potential Temperature, defined as
$$\theta_e = \theta \cdot e^{qL/c_pT}$$
with $\theta$ denoting potential temperature and q the specific moisture of water remains constant for wet ...
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What was this historic object used for?
This object is displayed in an exhibition, but nobody knows what it is.
It was part of the estate of a photographer whose father was one of the first meteorologists in Switzerland.
EDIT:
Adding more ...
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Why atmospheric temperature lapse rate doesn't have a discontinuity at 0°C when ice is formed?
When trying to calculate the adiabatic lapse rate of moist air based on known values of basic thermodynamic properties of the constituents (ice, water, vapor,...) I came to the following question:
...
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How much average temperature increase in India is due to Urbanisation and population growth?
There is an article on the BBC talking about an alarming increase of heatwaves in India. It also says that:
Average temperatures in India have risen by around 0.7% between 1901 and 2018,
partly due ...
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Why is latent heat of water vapor included in specific enthalpy of moist air?
In a lecture book we read about latent heat of moist air.
I would have guessed, that the total specific enthalpy of moist air, comprised of $m_d$ kg of dry air and $m_v$ kg of water vapor is (we have ...
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Confusion with thermal wind mechanism
In meteorology, we know that cold air mass sinks while warm air mass rises due to density difference, resulting in higher pressure in cold air mass. This leads to a horizontal pressure gradient from ...
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Altocumulus lenticularis - Why is this not considered a "strati-form type cloud
Of the major cloud families, the "cumulus" type (including stratocumulus, altocumulus and so on) are generally formed by convection in unstable air, leading to their "lumpy" or &...
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Correlation between cloud height and radius
Is the horizontal radius of a cloud correlated in some way with the cloud height, or are these two independent variables?
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Do snow gustnadoes or anything similar occur at or near the summits of the highest Himalayas such as Mt Everest?
A gustnado is a landspout (i.e. a "mini-tornado") that isn't connected to the ambient cloud base (if there is any). Mt Everest, the highest point on Earth, there is nothing "in the way&...
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What is a rough estimate for the number of people who have been in a tornado in their lifetime?
Discussing the relative risk of tornadoes vs earthquakes with a friend got me thinking about roughly how many people have been in tornadoes in their lifetime, which may be a statistic that would help ...
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Safest place on Earth during the pole shift
Where is the safest place on Earth in relation the magnetic poles as it is moving that will provide the most protection against solar radiation? I imagine the topography may effect the magnetic fields....
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Was the Earth a lot foggier millions of years ago?
Quoting a sign in Redwood National Park:
Redwoods once covered large expanses of the world. Millions of years ago some of these redwoods were preserved as fossilized trees when volcanic ash buried ...
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Do I understand pressure coordinates in the right way?
The question is simple: I still have problems with atmospheric pressure coordinates:
Given the pressure dependence in the picture, what are the velocity coordinates of an air parcel moving with $\vec ...
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How is Wind oriented in a Jet Streak?
Recently I found this tutorial video about Jet streaks (want to mention I'm only in second term so my knowledge is not advanced yet). Originally I was looking for the topic because of a particular ...
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What is 0 degree isotherm and how to calculate it?
I want to look at different areas of alpine glaciers and understand the position of 0 degree isotherm to do a comparative climate analysis. Given the mean annual air temperature and altitude, how do i ...
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My snarky cousin tossed a monkey into my ability to see large cloud at 300 miles HELP!
The top of a cumulonimbus cloud is usually about 40,000 feet and can reach heights of over 60,000 feet, which would be visible for a distance of 245 or 300 miles, respectively. from How far away can ...
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Estimating atmospheric vertical motion from 3D fields in WRF output
I have WRF data on isobaric levels that unfortunately does not contain a z-wind or omega field within the output, and I would like to produce some estimate as to the magnitude of synoptic-scale ...
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How to deduce the atmospheric mixed time-space domain energy cycle formulae, and where can Arpe et al. (1986) be found?
(Where can I know) How these formulae in the figure (Ulbrich and Speth, 1991), called mixed space-time domain formulation of the energy cycle, were deduced?
And the reference Arpe et al. (1986), I can ...
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Is it possible to calculate dew point at pressure levels from ERA5 data?
I would like to calculate dew point values at different pressure levels from the ERA5 data set. Is this possible and if so, how exactly can it be done? I have found an approximate formula that use ...
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Is there an open high frequency (1-0.2 Hz) wind measurement dataset from a marine station?
I want to conduct a statistical analysis of high-frequency wind measurements. This analysis aims to define relevant parameters for competitive coastal sailboat racing so the sampling frequency should ...
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