All Questions
Tagged with weather or meteorology
1,216 questions
11
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3
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Is it right practice to validate temperature data with reanalysis data?
For a project I am working on I received raw data from many meteorology stationes.
Is it right practice to test this data against air temperature from noaa's ncep/ncar data?
- 425
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2
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2k
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Is the southern hemisphere colder than the northern one or is it just me?
When comparing the same latitude at each hemisphere I've got the impression that the southern hemisphere is generally colder.
Tasmania and New Zealand's North Island for instance are around 36-43 ...
- 133
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2
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8k
views
How can I plot a Skew-T log-P diagram?
For displaying atmospheric soundings the use of Skew-T Log-P diagrams is very common. The manual THE USE OF SKEW T, LOG P DIAGRAM IN ANALYSIS AND FORECASTING from the Air Weather Service explains what ...
- 1,681
11
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3
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377
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Does finer input data lead to a better model accuracy?
Climate and chemical transport models all need input files including meteorology data, emission inventory, surface data (e.g. land use type) to initialize the simulation field.
Take the case of WRF ...
- 2,489
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2
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42k
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Have two hurricanes ever merged? And what was the result?
I was just reading this about how Hurricane Ethel could have merged with Hurricane Dora in 1964.
Has such a merge ever happened before in history? If so, what was the result? Would storms become ...
- 2,195
11
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1
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44k
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Why does it rain more at night than during the day?
I'm living near a sea, and it rains mostly and heavily at night from 11 PM to 3 AM. The weather is mostly clear during daytime.
Air is generally cooler at night, and cool air holds less moisture ...
- 213
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2
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210
views
What ice phenomenon are we seeing in this video?
I don't know what this YouTube video shows, but it appears to be half glacier and half "the blob." It almost appears to be "growing" although I assume it's being pushed somehow.
Can someone tell me ...
- 211
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1
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864
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Resources for learning the technical parts of atmospheric modeling
I'm a computer/atmospheric science undergrad and I'm trying to get into atmospheric modeling. Any recommendations for resources to get going or to learn about approaches? I can handle fairly technical ...
- 219
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2
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397
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How do meteorologists grade their past forecasts?
In every professional field, practitioners may come home at the end of the day and say "Yeah! I knocked it out of the park!", or alternatively "Oh, man. Gotta do better tomorrow." What about ...
- 1,178
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1
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6k
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Why is the South Pole colder than the North Pole?
This question popped into my head because I am designing a fictional world map, and I was wondering what factors influence the amount of ice at poles.
I want to know why there is much more ice ...
- 213
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1
answer
3k
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Why is Montana warmer than Wyoming?
The National Climatic Data Center (NCDC) data shows the mean temperature from 1971-2000 for Montana was 5.97°C (42.74°F) and Wyoming's was 5.54°C (41.98°F).
Montana is at a higher latitude, so this ...
- 7,827
11
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2
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741
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What are Atmospheric Rossby Waves and how do they affect the weather?
I've been researching Atmospheric Rossby waves but from the multiple sources I used they all seem to be in conflict. Some say Rossby waves are parcels of air moving from east to west due to the ...
- 113
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2
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2k
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How can daily brightness be quantified or measured?
It occurred to me that there might very will be a metric out there that measures and quantifies "daily brightness". Meaning, how bright any given day is, taking weather conditions and cloud coverage ...
- 213
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2
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466
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Propagation of sound after lightning
In an area of frequent thunderstorms, I notice a 'crack or whoosh' sound if a strike is nearby but little or no thunder. Yet I can hear for 30 seconds or so after a distant flash when the thunder ...
- 135
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1
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3k
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Has a hurricane or cyclone ever reformed after passing over a large land mass?
Hurricane Michael recently hit Florida as a Category 4 storm, and after the remnants passed across a great deal of the east coast of the United States it appears to have re-emerged into the Atlantic ...
- 213
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1
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428
views
How are low pressure zones tracked across the ocean?
When you look at a surface pressure chart e.g.:
(from http://www.metoffice.gov.uk/public/weather/surface-pressure/#?tab=surfacePressureColour&fcTime=1437480000)
you can see low pressure zones ...
- 213
11
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1
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4k
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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.
- 223
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1
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871
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Does the global temperature vary daily (hotter and colder days)?
Earth's current average global temperature (i.e. including hot deserts and cold polar caps) is reported be somewhere between 14°C and 16°C (depending on sources and methods).
This temperature varies ...
- 223
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2
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2k
views
Can an Atlantic hurricane enter Mediterranean sea?
I can't find any examples, has it just never happened before or is it impossible because of environmental factors?
- 1,389
11
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1
answer
732
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What is the motivation of using the Enhanced Fujita Scale in place of the Fujita Scale?
In 2007, the US started using an Enhanced Fujita Scale in place of the Fujita Scale. From a "civilian's" perspective, the Fujita Scale seemed to measure wind whereas the Enhanced Fujita Scale measures ...
user402
11
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1
answer
1k
views
Why does the meandering pattern of the jet stream itself propagate?
It is well known that the jet stream follows an overall meandering pattern, but what is less well known is that this meandering pattern itself moves as a wave with a velocity much slower than the ...
- 7,626
11
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1
answer
8k
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What causes the 'calm before the storm'?
The old adage "The calm before the storm" certainly has an observational scientific meaning to it -- something that many (including myself) have experienced -- that on a hot summer's day, when a ...
user889
11
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1
answer
2k
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How much energy is needed to alter the path of a hurricane?
Suppose we spot an Atlantic hurricane very early. How much energy should we expend to alter its track:
with nuclear detonations (let's forget about the side effects for the moment)?
with a large ...
- 2,103
11
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2
answers
847
views
How do we measure (or empirically calculate) the amount of entropy in the atmosphere and oceans?
Here's a paper on the entropy budget1, where moist entropy is defined in equation (8) as
$$
s = (1-q_t)(C_{pd} \ln T - R_d \ln p_d) + q_t C_l \ln T + \frac{q_v L_v}{T} - q_v R_v \ln \mathcal{H}
$$
...
- 7,827
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3
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676
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How much does COVID-19 affect weather forecasts?
The World Meteorological Organization (WMO) is concerned about the impact of the COVID-19 pandemic on the quantity and quality of weather observations and forecasts, as well as atmospheric and climate ...
- 231
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1k
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Is increase in atmospheric $\mathrm{CO}_2$ concentration affecting Earth's atmospheric pressure?
It's well known that the $\mathrm{CO}_2$ levels around the world are increasing, leading to an increase in overall surface temperature, etc.
But I'm wondering, are these gases (or the effects from ...
- 333
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1
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3k
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Why do tropical cyclones around Australia have erratic paths?
According to the Australia Bureau of Meterology:
Research has shown that cyclones in the Australian region exhibit more
erratic paths than cyclones in other parts of the world. A tropical
...
- 4,427
11
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1
answer
507
views
Optimal vertical coordinate for complex topography
There are plenty of choices in models in so far as choice of vertical coordinate is concerned for meteorological models.
Five that I know of:
The sigma coordinate system - Hybrid coordinate system(...
user1066
11
votes
1
answer
8k
views
What are the key differences between warm and cold core cyclones?
What are the key differences between warm and cold core cyclones? What is an example of each?
- 2,658
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1
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2k
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What is the difference between an inertial instability and a symmetric instability?
Inertial and symmetric instabilities are fluid instabilities present in atmosphere and ocean.
What are the difference between an inertial instability and a symmetric instability?
- 211
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1
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266
views
How to statistically downscale wind speeds?
Background
I am trying to estimate wind speeds at a proposed wind farm site using the method described in this paper: Modeling of Ethiopian Wind Power Production Using ERA5 Reanalysis Data. The ...
- 251
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1
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237
views
Synoptic weather predictibility under climate change scenarios
Under climate change scenarios, it is quite certain that high latitude regions will experience more warming than at low latitudes. For example, in winter the reduced area of sea ice and snow cover ...
- 363
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0
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3k
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Intuitive explanation of precipitation amount [duplicate]
I'm trying to learn how to make sense of numbers in a forecast. I can interpret temperature and wind speed, but I don't know what to make of rainfall. What does it mean, for a human, that there will ...
- 111
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2
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1k
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Are weather forecast models more accurate for either high or low temperatures?
The other day our low temperature for the day was ~10 degrees F below our forecast low. I've noticed this before in the winter, especially when temperatures start to go below 0 degrees F (-18 degrees ...
user11318
10
votes
3
answers
672
views
Why don't weather forecast models normally take solar eclipses into account?
Since there is a total solar eclipse somewhere almost every year, I would have thought it would be included as a standard option in weather forecast models. However, I've learned that is not really ...
- 14k
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3
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15k
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What does the notation "kg kg-1" for units mean for specific humidity
I am using a data set from Justin Sheffield at Princeton that includes specific humidity. The description is as follows:
"Reanalysis 6-hourly specific humidity interpolated to 1.0deg with account ...
- 667
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3
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2k
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Can volcanos change the climate?
I have heard politicians claiming that volcanoes are the sole cause of global warming and using so called "NASA data" to show that the Earth is actually cooling instead of warming.
While the nature ...
- 1,932
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2
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2k
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Why is q used for specific humidity?
$q$ is the symbol used for specific humidity in many textbooks and papers (at least in meteorology and climatology, I'm not familiar with it in other disciplines). Where does this symbol come from, ...
- 5,435
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2
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7k
views
What causes a rainbow, its colours and its shape?
What is the cause of rainbows? Do they appear due to rainfall or any other natural phenomenon. What makes it form a semi-circle in the atmosphere and its colours?
- 628
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3
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565
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Predicting school closures with historical weather prediction data?
I'm interested in predicting when the local schools will be closed due to snow and other winter weather. I have a list of school closure dates and a rough sense of the criteria used to determine the ...
- 201
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2
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2k
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What is this spaceship-shaped cloud?
This tweet from the European Space Agency (ESA)'s Spanish account show a striking photo of a round, flat, "space-ship-shaped" cloud in an otherwise completely clear sky. The stars are out so I assume ...
- 6,904
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1k
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What are the sunniest places on Earth? (including oceans)
This question did arise when thinking on offshore solar power plants, what's their potential, and how efficient would they be compared with land based counterparts.
Recently, it is becoming more ...
- 373
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14k
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Is it typically colder after a storm?
I've heard that it's colder after a storm. I think this is an interesting question, not least because of the implicit comparison: colder than what? A few different comparisons come to mind, and still ...
- 201
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2
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1k
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Can the Bering Sea Rule be used to predict the weather?
Recently, a colleague explained that the recent cold spell in the eastern United States could have been predicted using the Bering Sea Rule. The idea is that 17-21 days after a storm appears in the ...
- 15.5k
10
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2
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501
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Does lapse rate apply below sea level?
In many parts of the world there are dry lands below sea level, such as parts of the Netherlands. Since we know that temperature decreases with increasing altitude, does it mean that temperature will ...
- 203
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1
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2k
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How to calculate relative humidity?
I am involved in developing a weather based application which needs to calculate relative humidity and display it. I grab other weather variables like temperature, precipitation, wind speed and ...
- 101
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2
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335
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Why does the rising of high clouds due to climate change impart positive radiative feedback on radiative forcing?
As seen in the figure below.
The larger the temperature difference between surface and cloud, the more positive the radiative forcing is from the cloud.
So as the cloud moves up, it supposedly ...
- 7,827
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1
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424
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Unstable North Polar Vortex?
What would cause a polar vortex to become unstable a split into 3 smaller ones? How rare is this and what long term effects could this cause if the vortex stays unstable?
http://www.severe-weather.eu/...
- 1