Identification

Title

Estimates of past and future ozone trends from multimodel simulations using a flexible smoothing spline methodology

Abstract

A novel additive model analysis of multimodel trends is presented. The approach is motivated by, and particularly suited to, the analysis of multimodel time series of varying length. This Time series Additive Model (TSAM) approach consists of three distinct steps: estimation of individual model trends, baseline adjustment of the trends, and the weighted combination of the individual model trends to produce a multimodel trend (MMT) estimate. The baseline adjustment step is not an essential ingredient of the TSAM but is included to reduce model spread. The association of the TSAM approach with a probabilistic model allows trend estimates to be used to make formal inference (e.g., calculation of confidence and prediction intervals). The method is applied to the analysis of multimodel ozone time series of varying lengths as were considered for the 2006 Scientific Assessment of Ozone Depletion. The advantages of the TSAM approach are demonstrated to include the production of smooth trend estimates out to the ends of the time series, the ability to model explicitly interannual variability about the trend estimate, and the ability to make rigorous probability statements. Calculated ozone return dates are consistent with previous qualitative estimates, but the more quantitative analysis provided by the MMT is expected to allow such data sets to be better utilized by the community and policy makers.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d74m954v

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

2010-11-24T00:00:00Z

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