In 2015, annual average atmospheric carbon dioxide (CO2) levels surpassed a level of 400 parts per million (ppm) for the first time in three million years. This has caused widespread concern among climate scientists, and not least among those that work on natural climate variability in prehistoric times, before humans. These people are known as "past climate" or palaeoclimate researchers, and author Eelco J. Rohling is one of them. Based on the Research School of Earth Sciences, The Australian National University, Canberra, he has previously authored The Oceans: A Deep History. The Climate Question offers a background to these concerns in straightforward terms, with examples, and is motivated by Rohling's personal experience in being intensely quizzed about whether modern change is not all just part of a natural cycle, whether nature will not simply resolve the issue for us, or whether it won't be just up to some novel engineering to settle things quickly.
The Climate Question discusses in straightforward terms why climate changes, how it has changed naturally before the industrial revolution made humans important, and how it has changed since then. It compares the scale and rapidity of variations in pre-industrial times with those since the industrial revolution, infers the extent of humanity's impacts, and looks at what these may lead to in the future. Rohling brings together both data and process understanding of climate change. Finally, The Climate Question evaluates what Mother Nature could do to deal with the human impact by itself, and what our options are to lend her a hand.
1. Introduction
2. Past climates: How We Get Our Data
- Data from ice
- Data from land
- Data from the sea
- Data about sea-level changes
- Recap and outlook
3. Energy balance of climate
- The greenhouse gases
- A perspective from studies of past climates
- Recap and outlook
4. Causes of climate change
- Carbon-cycle changes
- Astronomical variability
- Large (super-)volcanic eruptions, and asteroid impacts
- Variability in the intensity of solar radiation
- Recap and outlook
5. Changes during the industrial age
- Direct effects
- Global responses and climate sensitivity
- Sea-level change
- Common reactions to the geological perspective
- Recap and outlook
6. Mother Nature to the rescue?
- Weathering, reforestation, and carbon burial
- Requirement for human intervention
-Human intervention in carbon removal
7. Summary
8. Epilogue
Glossary
Acknowledgements
References and notes
Eelco J. Rohling is based at the Research School of Earth Sciences, The Australian National University, Canberra (since 2013), and secondarily affiliated with the University of Southampton, National Oceanography Centre Southampton, UK (since 1994). His research focuses on ocean and climate change with emphasis on sea level, climate sensitivity, and past episodes of enhanced carbon burial in ocean sediments.