Constraining the Nineteenth-Century Temperature Baseline for Global Warming

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F86652079%3A_____%2F23%3A00575274" target="_blank" >RIV/86652079:_____/23:00575274 - isvavai.cz</a>

Result on the web

<a href="https://journals.ametsoc.org/view/journals/clim/36/18/JCLI-D-22-0806.1.xml" target="_blank" >https://journals.ametsoc.org/view/journals/clim/36/18/JCLI-D-22-0806.1.xml</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1175/JCLI-D-22-0806.1" target="_blank" >10.1175/JCLI-D-22-0806.1</a>

Result language

angličtina

Original language name

Constraining the Nineteenth-Century Temperature Baseline for Global Warming

Original language description

Since the Paris Agreement, climate policy has focused on 1.5 & DEG and 2 & DEG C maximum global warming targets. However, the agreement lacks a formal definition of the nineteenth-century ,,pre-industrial,, temperature baseline for these targets. If global warming is estimated with respect to the 1850-1900 mean, as in the latest IPCC reports, uncertainty in early instrumental temperatures affects the quantification of total warming. Here, we analyze gridded datasets of instru-mental observations together with large-scale climate reconstructions from tree rings to evaluate nineteenth-century base-line temperatures. From 1851 to 1900 warm season temperatures of the Northern Hemisphere extratropical landmasses were 0.20 & DEG C cooler than the twentieth-century mean, with a range of 0.14 & DEG -0.26 & DEG C among three instrumental datasets. At the same time, proxy-based temperature reconstructions show on average 0.39 & DEG C colder conditions with a range of 0.19 & DEG -0.55 & DEG C among six records. We show that anomalously low reconstructed temperatures at high latitudes are underrep-resented in the instrumental fields, likely due to the lack of station records in these remote regions. The nineteenth-century offset between warmer instrumental and colder reconstructed temperatures is reduced by one-third if spatial coverage is reduced to those grid cells that overlap between the different temperature fields. The instrumental dataset from Berkeley Earth shows the smallest offset to the reconstructions indicating that additional stations included in this product, due to more liberal data selection, lead to cooler baseline temperatures. The limited early instrumental records and comparison with reconstructions suggest an overestimation of nineteenth-century temperatures, which in turn further reduces the prob-ability of achieving the Paris targets.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10509 - Meteorology and atmospheric sciences

Project

<a href="/en/project/EF16_019%2F0000797" target="_blank" >EF16_019/0000797: SustES - Adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Climate

ISSN

0894-8755

e-ISSN

1520-0442

Volume of the periodical

36

Issue of the periodical within the volume

18

Country of publishing house

US - UNITED STATES

Number of pages

12

Pages from-to

6261-6272

UT code for WoS article

001053856600001

EID of the result in the Scopus database

2-s2.0-85171892455