MASS-UMAP: Fast and Accurate Analog Ensemble Search in Weather Radar Archives

Autor: Gabriele Franch, Marta Pendesini, Giuseppe Jurman, Luca Coviello, Cesare Furlanello
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Remote Sensing; Volume 11; Issue 24; Pages: 2922
ISSN: 2072-4292
DOI: 10.3390/rs11242922
Popis: The use of analog-similar weather patterns for weather forecasting and analysis is an established method in meteorology. The most challenging aspect of using this approach in the context of operational radar applications is to be able to perform a fast and accurate search for similar spatiotemporal precipitation patterns in a large archive of historical records. In this context, sequential pairwise search is too slow and computationally expensive. Here, we propose an architecture to significantly speed up spatiotemporal analog retrieval by combining nonlinear geometric dimensionality reduction (UMAP) with the fastest known Euclidean search algorithm for time series (MASS) to find radar analogs in constant time, independently of the desired temporal length to match and the number of extracted analogs. We show that UMAP, combined with a grid search protocol over relevant hyperparameters, can find analog sequences with lower mean square error (MSE) than principal component analysis (PCA). Moreover, we show that MASS is 20 times faster than brute force search on the UMAP embedding space. We test the architecture on real dataset and show that it enables precise and fast operational analog ensemble search through more than 2 years of radar archive in less than 3 seconds on a single workstation.
Databáze: OpenAIRE