This code replicates results from Arnscheidt and Rothman: Presence or absence ofstabilizing Earth system feedbacks on different timescales (2022).
data_analysis.py reads data provided in the isotope_data folder and analyzes how the typical amplitudes of temperature fluctuations depend on their timescale.
model_analysis.py conducts the same analysis for the two simple feedback models described in the main text. To save time and space, the results are saved in .npy files. However, they can be re-generated by running feedback_models.jl and uncommenting the appropriate lines in model_analysis.py
model_analysis.py conducts the same analysis for the two simple feedback models described in the main text. To save time and space, the results are saved in .npy files. However, they can be re-generated by running feedback_models.jl (to generate feedback_models_2.csv) and uncommenting the appropriate lines in model_analysis.py.
The paleotemperature data derives from the following sources (please cite if re-used!) The files are labeled accordingly.
- J. Zachos et al. “Trends, rhythms, and aberrations in global climate 65 Ma to present”. science 292.5517 (2001), pp. 686–693.
- J. C. Zachos, G. R. Dickens, and R. E. Zeebe. “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics”. Nature 451.7176 (2008), p. 279.
- L. E. Lisiecki and M. E. Raymo. “A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18 O records”. Paleoceanography 20.1 (2005).
- P. Huybers. “Glacial variability over the last two million years: an extended depth-derived age-model, continuous obliquity pacing, and the Pleistocene progression”. Quaternary Science Reviews 26.1-2 (2007), pp. 37–55.
- F. Parrenin et al. “Synchronous change of atmospheric CO2 and Antarctic temperature during the last deglacial warming”. Science 339.6123 (2013), pp. 1060–1063.
- T. Westerhold et al. “An astronomically dated record of Earth’s climate and its predictability over the last 66 million years”. Science 369.6509 (2020), pp. 1383–1387.
Please reach out to me (Constantin Arnscheidt; cwa@mit.edu) if you have any issues.