Nonlinear Processes in Geosciences

NPG Paper of the Month: “Application of a local attractor dimension to reduced space strongly coupled data assimilation for chaotic multiscale systems”

Tommaso Alberti April 23, 2020

Local dynamical properties of a segment of an example run for the coupled Lorenz system. (a) Alignment of directions of error growth plotted along the x coordinate of the ocean subsystem. Large orange stars indicate high alignment of error growth in the unstable or neutral subspaces. (b) Finite-time Lyapunov exponents (FTLEs) computed over window τ = 4. (c) Local Kaplan-Yorke dimension calculated from FTLEs. (Source: Quinn, O’Kane, and Kitsios, Application of a local attractor dimension to reduced space strongly coupled data assimilation for chaotic multiscale systems, Nonlin. Processes Geophys., 27, 51–74, 2020, https://www.nonlin-processes-geophys.net/27/51/2020/. License: https://creativecommons.org/licenses/by-nc-nd/4.0/.

This month the NPG Paper of the Month award is achieved by Courtney Quinn for her paper “Application of a local attractor dimension to reduced space strongly coupled data assimilation for chaotic multiscale systems” (https://www.nonlin-processes-geophys.net/27/51/2020/). Dr. Courtney obtained her PhD in Mathematics at the University of Exeter (UK) researching critical transitions in dynamical syst ...[Read More]

After Lorenzo and Ophelia, should we prepare European coasts for tropical storms and hurricanes?

Davide Faranda October 15, 2019

probability forecasts of tropical storm force winds issued by the National Hurrican Center issued on 02/10/2019. Source: https://www.nhc.noaa.gov/graphics_at3.shtml?tswind120? .

Autumn is hurricane season in the north tropics and indeed 2019 does not make exception from this point of view. After Dorian hitting Bahamas and North Carolina, the American National Hurricane Center named Lorenzo a tropical depression originating near Capo Verde. On September 25th Lorenzo became a category 1 hurricane, according to the Saffir-Simpson scale. This scale categorizes the hurricanes ...[Read More]

June Heatwave 2019: can we attribute the event to anthropogenic emission?

Davide Faranda July 25, 2019

2 meters GFS temperature anomalies with respect to the 1981-2010 CFSR climatology. Source http://www.tropicaltidbits.com.

If August Rodin had lived nowadays, he would have placed his gates of hell (la Porte de l’Enfer) in Gallargues-le-Montueux, where the absolute French temperature record (45.9 °C) was set on June 28th this year. The last week of June has been very hot, not only in the south of France, but overall central Europe: in the Alps, some locations such as Chamonix (France) and Aosta (Italy) experienced tem ...[Read More]

NP Interviews: the Division President Stéphane Vannitsem

Tommaso Alberti July 25, 2019

The Nonlinear Processes in Geosciences Division President Stéphane Vannitsem.

Today’s NP Interviews hosts the Nonlinear Processes Division President Stéphane Vannitsem. Stéphane is the head of the Dynamical Meteorology and Climatology Unit of the Research division of the Royal Meteorological Institute of Belgium, and lecturer at the Free University of Brussels. He is currently president of the Nonlinear Processes division of the European Geosciences Union and executive edit ...[Read More]