Viewing posts by Alexander Baker

Plot of the month (Mar 2019): 10km global modelling

Plot of the month for March 2019 showcases a 10km-resolution global simulation, performed by Pier Luigi Vidale.

This is a still from an animation created using output from HRCM's flagship global climate model, HadGEM3, run at a resolution of about 10km. The animation shows a typical year of simulation, with liquid and frozen water content integrated to show clouds; colours within clouds indicating amount of precipitation (rain and snow), sea ice and snow amounts shown at the surface with bright colours. Look for weather fronts at mid to high-latitudes, as well as tropical cyclones (hurricanes and typhoons) appearing in the season May to November in the Northern Hemisphere tropics: you should be able to spot the "eye" feature of those powerful storms.

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Plot of the month (Feb 2018): atmospheric blocking 'storymap'

Plot of the month for February 2018 is from the PRIMAVERA project as part of its user engagement activities, which explores the role atmospheric blocking plays in European weather and its effect on the energy sector.

Instead of the large-scale westerly flow that is typical of the North Atlantic, with the passage of low- and high-pressure systems and their associated cold and warm fronts, mid-latitude atmospheric blocking appears as large, quasi-stationary high-pressure systems (anti-cyclones). Atmospheric blocking is a stable atmospheric circulation that yields persistent weather over large regions for weeks to months.

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Plot of the month (Jan 2018): heavy precipitation from cyclones

Plot of the month for January 2018 is from Alexander Baker, who asks: how many wintertime heavy precipitation events can be attributed to extratropical cyclones?

Using ERA-Interim reanalysis data for the period 1979-2016, the number of heavy precipitation events coinciding with cyclones was quantified for the Northern Hemisphere, following a published method by Pfahl and Wernli (2012).

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Plot of the month (Nov 2017): extratropical storm in a 25km model

Plot of the month (November 2017) is from the PRIMAVERA project and shows how extratropical storms are represented in a high-resolution, 25 km global climate model.

Following on from previous posts, the figure below shows in detail how winds and precipitation, particularly along the trailing front and the maximum over France, are represented more realistically in a 25 km global model.

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