Publicly available data set with ensemble forecasts and observations?

Asked by: Robby Filippi

Why do we use ensemble forecasts?

Ensemble forecasting is a method used in or within numerical weather prediction. Instead of making a single forecast of the most likely weather, a set (or ensemble) of forecasts is produced. This set of forecasts aims to give an indication of the range of possible future states of the atmosphere.

What is ECMWF data?

ECMWF is the European Centre for Medium-Range Weather Forecasts. We are both a research institute and a 24/7 operational service, producing global numerical weather predictions and other data for our Member and Co-operating States and the broader community.

How are ensemble weather forecasts made with a single numerical forecast model?

It is created by estimating the current state of the atmosphere using observations, and then calculating how this state will evolve in time using a numerical weather prediction computer model. As the atmosphere is a chaotic system, very small errors in its initial state can lead to large errors in the forecast.

What is GFS data?

The Global Forecast System (GFS) is a National Centers for Environmental Prediction (NCEP) weather forecast model that generates data for dozens of atmospheric and land-soil variables, including temperatures, winds, precipitation, soil moisture, and atmospheric ozone concentration.

How many forecasts make an ensemble?

Modern ensemble forecasts have anywhere between 12 and 51 members, depending on the model.

How do ensemble models work?

Ensemble modeling is a process where multiple diverse models are created to predict an outcome, either by using many different modeling algorithms or using different training data sets. The ensemble model then aggregates the prediction of each base model and results in once final prediction for the unseen data.

Which is better GFS or ECMWF?

Statistically speaking, the very clear answer is that the ECMWF consistently performs better than the GFS, as the model skill score graph above shows.

How do I access ECMWF?

Just point your browser to the ECaccess login page and under the heading ‘Web session’, log in with your ECMWF uid and passcode.



Web session

1. Manage your files (browsing, deleting, copying, etc)
2. Transfer files.
3. Submit jobs and view the queues.

Who uses ECMWF?

ECMWF comprises 23 European countries: the eighteen founding states of 1975: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Republic of Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom.

How can ensemble forecasts improve Medium Range Weather Forecasts?

How can ensemble forecasts improve medium-range weather forecasts? They are made by running several simulations of a single model each with slightly different conditions. Meteorologists can use them to find what they all have in common.

What is an ensemble model meteorology?

ENSEMBLE. A collection of numerical model results that show slightly different possible outcomes. Ensemble Forecast. Multiple predictions from an ensemble of slightly different initial conditions and/or various versions of models.

What are numerical weather prediction models?

Numerical weather prediction (NWP) is a method of weather forecasting that employs a set of equations that describe the flow of fluids.

How do forecast models work?

These forecast models take current weather observations collected from thousands of locations (such as wind speed, wind direction, air temperature, pressure, etc.), make an estimate about the current weather for locations where no actual data exists, and then use math and physics equations to predict what will happen

What is multi model ensemble?

Multi-model ensembles are defined in these studies as a set of model simulations from structurally different models, where one or more initial condition ensembles are available from each model (if more initial conditions for each model are available the experiments are often said to make up a super-ensemble).

What is EPS ensemble?

Ensemble Prediction Systems (EPS) are numerical weather prediction (NWP) systems that allow us to estimate the uncertainty in a weather forecast as well as the most likely outcome.

How can ensemble forecasts improve Medium Range Weather Forecasts?

How can ensemble forecasts improve medium-range weather forecasts? They are made by running several simulations of a single model each with slightly different conditions. Meteorologists can use them to find what they all have in common.

What is multi model ensemble?

Multi-model ensembles are defined in these studies as a set of model simulations from structurally different models, where one or more initial condition ensembles are available from each model (if more initial conditions for each model are available the experiments are often said to make up a super-ensemble).

What is ensemble dispersion?

4.1 Ensemble Dispersion and What It Tells Us. Dispersion describes the climatological range of an ensemble forecast system relative to the range of the observed outcomes. This diagram shows three scenarios with ensemble forecasts (dark green line) plotted with verifying observations (brown line).

What is EPS ensemble?

Ensemble Prediction Systems (EPS) are numerical weather prediction (NWP) systems that allow us to estimate the uncertainty in a weather forecast as well as the most likely outcome.

What is Ecmwf ensemble?

The European Centre for Medium-Range Weather Forecasts (ECMWF) has pioneered a system to predict forecast confidence. This system, operational at ECMWF since 1992, is the Ensemble Prediction System (EPS). The rationale behind probabilistic weather forecasts.

What is the Ecmwf forecast model?

ECMWF’s operational forecasts aim to show how the weather is most likely to evolve. To do this, the Centre produces an ensemble of predictions. Individually they are full descriptions of the evolution of the weather. Collectively they indicate the likelihood of a range of future weather scenarios.