Identification

Title

Modeling European hot spells using extreme value analysis

Abstract

Atmospheric blocking in mainland Europe is often cited as the cause of extremely high temperatures lasting several days. By definition, extreme temperatures are rare, and yet the theory of extreme value statistics has seldom been applied to quantify the influence of atmospheric blocking on hot spells. Similarly, a comparison of the relative influence of other well-known atmospheric drivers, such as the North Atlantic Oscillation (NAO) and the El Nino-Southern Oscillation (ENSO), has seldom been explored. We applied a novel combination of extreme value and geometric distributions to observed daily temperature maxima from 74 stations across Europe, covering 1951-2010, to establish a stationary model of the expected magnitude, frequency and duration of hot spells that did not explicitly account for atmospheric drivers. Monthly time series of NAO, ENSO and 4 coherent atmospheric blocking regions were then incorporated as non-stationary covariates in the distribution parameter estimates to assess the dependence of hot spells on atmospheric covariates. We concluded that ENSO does not have a significant influence on hot spell magnitude or frequency; the NAO is a significant driver of hot spell magnitude (maximum attained temperature), frequency (annual event count) and duration (length of event) in northern Europe and Atlantic bordering stations; and atmospheric blocking is a significant driver of all aspects of hot spells in all parts of Europe. While NAO may increase peak temperatures by 2-4 degrees C only in the north, relatively strong atmospheric blocking could result in increased temperatures of at least 4 degrees C higher across Europe, with a commensurate increase in hot spell duration of 2-4 d.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7ww7kfp

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2014-01-07T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact