Related Experiment Video
Updated: Jul 14, 2026
13:27
Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
9.3K
A large ozone-circulation feedback and its implications for global warming assessments.
Peer J Nowack1, N Luke Abraham2, Amanda C Maycock3
1Centre for Atmospheric Science, Department of Chemistry, University of Cambridge, Cambridge, United Kingdom.
Nature Climate Change
|March 3, 2015
Summary
Accurate representation of stratospheric ozone is crucial for climate sensitivity estimates. Ignoring ozone feedbacks in climate models can lead to significant overestimations of global warming, impacting future climate projections.
Area of Science:
- Climate modeling
- Atmospheric chemistry
- Radiative transfer
Background:
- Modern climate models incorporate complex processes at high resolutions.
- Computational expense often leads to the exclusion of atmospheric chemical feedbacks in simulations.
- Stratospheric ozone representation is a critical, yet often simplified, component in climate modeling.
Purpose of the Study:
- To investigate the impact of stratospheric ozone representation on effective climate sensitivity.
- To quantify the influence of ozone feedbacks on global mean surface warming under increased CO2 forcing.
- To highlight implications for climate model intercomparison studies.
Main Methods:
- Utilized a comprehensive atmosphere-ocean chemistry-climate model.
- Compared simulations with prescribed pre-industrial ozone levels versus self-consistent ozone evolution.
- Applied an abrupt 4xCO2 forcing scenario.
Main Results:
- Prescribing pre-industrial ozone levels resulted in a ~1°C (20%) increase in global mean surface warming over 75 years compared to self-consistent ozone.
- This difference is attributed to radiative feedbacks from circulation-driven decreases in tropical lower stratospheric ozone.
- Observed changes in stratospheric water vapor and cirrus clouds contributed to the warming discrepancy.
Conclusions:
- Stratospheric ozone feedbacks significantly influence effective climate sensitivity estimates.
- Simplified treatments of atmospheric composition in climate models can lead to inaccurate warming projections.
- Accurate representation of ozone-chemistry-climate interactions is vital for reliable climate change assessments.
Related Concept Videos
01:14The Carbon Cycle
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
01:07What is Weather?
Overview
01:16What is Climate?
Climate refers to the prevailing weather conditions in a specific area over an extended period. As the saying goes, “Climate is what you expect. Weather is what you get.” Climate is influenced by geographic factors, such as latitude, terrain, and proximity to bodies of water.
01:50Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
01:17Radiation: Applications
The average temperature of Earth is the subject of much current discussion. Earth is in radiative contact with both the Sun and dark space; it receives almost all its energy from the radiation of the Sun and reflects some of it into outer space. Dark space is very cold, about 3 K, so Earth radiates energy into it. For instance, heat transfer occurs from soil and grasses, the rate of which can be so rapid that frost can occur on clear summer evenings, even in warm latitudes.
The average...
The average...
01:27Microbes and Climate Change
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...