Identification

Title

Regional and seasonal hydrological changes with and without stratospheric aerosol intervention under high greenhouse gas climates

Abstract

Stratospheric aerosol intervention (SAI) is being explored for its potential to reduce greenhouse gas (GHG) induced climate damages. We assess the effectiveness of two SAI experiments, G6Sulfur and Geo SSP5‐8.5 1.5 (here called Geo‐SAI), using the CESM2(WACCM6) model to reduce hydrological changes under high‐emission SSP5‐8.5 (no mitigation) pathway. Geo‐SAI stabilizes near surface global temperatures at 1.5°C above preindustrial levels, whereas G6Sulfur limits temperature rises to those under the SSP2‐4.5 scenario. In our findings, Geo‐SAI reverts many, but not all, hydrological changes induced by SSP5‐8.5 restoring global and regional means, seasonal amplitudes, and peak timings. G6Sulfur delivers smaller restorations, as expected, due to its smaller prescribed forcing. In hyperarid regions such as the Middle East, both SAI scenarios improve water storage compared with both SSP5‐8.5 and present conditions. However, in wetter or cooler climates, such as the Amazon, middle and southern Africa and east Europe, they only partly reverse the reductions in available water (AW) and runoff caused by high GHG emissions. Residual warming and snowmelt dynamics play an important role in runoff at mid‐to‐high latitudes. Additionally, SAI does not completely suppress GHG‐induced vegetation expansion and so over‐reduces global runoff in three latitude bands: 45°–65°N, 45°–65°S, and 30°S to 0 with end‐of‐century decreases of 4.1% under G6Sulfur and 7.3% under Geo‐SAI despite mean AW levels remaining close to present‐day. These findings emphasize that although SAI mitigates many climate‐driven hydrological disruptions, its unintended effects on runoff, vegetation feedback, and regional water availability warrants study—especially in regions heavily dependent on surface water resources.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.net/ark:/85065/d7jm2g36

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

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South bounding latitude

Temporal reference

Temporal extent

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End position

Dataset reference date

date type

publication

effective date

2025-06-28T00:00:00Z

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