Objective Identification and Climatic Characteristics of Heavy
Precipitation Northeastern China Cold Vortex Events
Abstract
The northeastern China cold vortex (NCCV) has an important influence on
the regional rainstroms over East Asia. Using the National Centers for
Environmental Prediction Final (FNL) reanalysis dataset and the Global
Precipitation Measurement product, an improved objective algorithm for
identifying heavy precipitation NCCV (HPCV) events from 2001 to 2019 was
designed. The climatological features of 208 HPCV events were
investigated. The number of HPCV events showed an upward linear trend,
with the highest frequency of occurrence in summer. The most active
region of HPCVs was in the Northeast China Plain of 40–55° N. Most HPCV
events lasted 2–5 days and had radii ranging from 250 to 1000 km. About
79% of the HPCV events was initiated (dissipated) in the definition
region (35–60° N, 115–145° E). The initial position was close to the
western boundary of the definition region, and the final position was
mainly in the first and the fourth quadrants. The HPCV events that moved
into the study region had a longer duration than those initiating in the
region. The monthly variation of the strongest precipitation in the HPCV
events showed a bimodal pattern, with two peaks in June and October. The
location of the strongest precipitation was mostly concentrated within
2000 km southeast of the HPCV systems and it had a strong positive
correlation with the center of HPCV events.