Questions tagged [nwp]

NWP is Numerical Weather Prediction: the use of numerical models to produce weather forecasts for operational purposes.

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1answer
243 views

How do spectral methods work in the context of numerical weather prediction models?

I am broadly familiar with the concept of numerical weather prediction models using various finite methods to solve the primitive equations used in these models, but how do spectral methods work, ...
3
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3answers
869 views

Predicting rainfall with governing equations

Which model is a good starting point for predicting precipitation (rain) for 24 hours in advance? I looked at Kalnay's Atmospheric modeling, data assimilation and predictability, and Holton's An ...
3
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1answer
470 views

How to properly setup a domain in NWP model (WRF) according to meteorological input data

I want to setup a mesoscale weather prediction model (WRF or something else) to work with NCEP/GFS meteorological input data with resolution of 0.25deg. My question is how to choose a proper size for ...
5
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1answer
190 views

Timeline of atmospheric model resolution

I'm looking for a graph of improvements in spatial resolution for any atmospheric model (such as the UK Met Office Unified Model or ECMWF IFS). Ideally it would include a range of historical model ...
10
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2answers
334 views

The origin of spurious high frequency waves in numerical weather prediction

I am currently reading this paper on digital filters and their relevance to meteorological models Digital Filter Initialization . My question relates to this following text - "The requirement to ...
12
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1answer
1k views

Numerical weather forecasting - resources for a programmer?

There is a community wiki question over at A good book or source for climate science and meteorology basics? that talks about meteorology basics. Building on that, but with a slightly different focus,...
11
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1answer
234 views

Equation for predicting contrail formation

I am working on a data visualisation of airline flight paths and their probability of forming contrails. Given weather data for a specific area (location, time, temperature, pressure and humidity) ...
18
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2answers
4k views

What are the applications of hydrostatic solvers vs non-hydrostatic solvers in numerical weather prediction?

In the atmospheric dynamics research community, many colleagues of mine happen to use atmospheric models that have non-hydrostatic equation solvers, e.g. the UK MetOffice model, and WRF-ARW: The ...
12
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3answers
5k views

What are the differences between implicit and explicit methods when applied to modelling Earth systems?

I am struggling to understand the difference between implicit methods and explicit methods in numerical modelling of Earth processes, particularly when applied to modelling Earth systems in 2 or more ...
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2answers
174 views

What determines the differences in results between various weather models?

It's often said that the ECMWF model is more accurate than the GFS. But what are the reasons why? Also, how does the NAM compare with these two and other forecasting models?
13
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2answers
174 views

Are clouds significantly easier to simulate in weather models than climate models?

Cloud forcing is still one of the major uncertainties of radiative forcing in climate modeling because there are so many uncertainties in it (and parametrizations). But also because the timescale of ...
12
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2answers
378 views

Bifurcation Scenarios in the Atmosphere

I read that the mathematical definition of bifurcation is that, at a critical value of a parameter that governs the dynamical system, the system changes to a topologically different system than the ...
18
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1answer
354 views

How is global weather model skill measured?

The models I have in mind are the major global models such as the Global Forecast System (GFS) and the European Center for Medium range Weather Forecasting (ECMWF). These models produce numerous ...
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1answer
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How can I estimate a 2 m temperature from / in an atmospheric model?

Numerical models of the atmosphere usually have their first atmospheric grid level well above 2 m, but the temperature at 2 m above ground level is something one often wants to calculate with such a ...
8
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1answer
60 views

Are Argo probe data used for numerical weather prediction (NWP)?

Argo probes broadcast surface measurements (among other things) on the worlds oceans, far away from traditional surface observations. Yin et al. (2010) study the assimilation of these measurements in ...
29
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4answers
3k views

How do weather models work?

We use different weather models all the time, such as the ECMWF and the GFS. These models are simply amazing to me. How do these models work? I know they have to take in various data points - what ...