Causality in climate and hydrology

A. Christofides, and D. Koutsoyiannis, Causality in climate and hydrology, European Geosciences Union General Assembly 2011, Geophysical Research Abstracts, Vol. 13, Vienna, EGU2011-7440, doi:10.13140/RG.2.2.33776.46082, European Geosciences Union, 2011.



We often see statements such as “90% of climate change is caused by X” and debates on whether the dominant cause of climate change is human activity, or the sun, or something else. However, in chaotic systems, it can be difficult to defend the meaning of such assertions, because if the “effect” occurs sufficiently later than the supposed “cause”, the relationship between the two is effectively lost because of the sensitivity of the “effect” to the initial conditions. In fact, although “A causes B” initially seems clear, closer examination of what it actually means reveals problems that have tortured philosophers for centuries. We review the meaning of causation in the context of hydroclimatology as well as its possible reformulation in probabilistic terms.

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Related blog posts and discussions can be seen in Climate Science: Roger Pielke Sr., Bishop Hill,, Climate Etc.: Judith Curry.

Our works referenced by this work:

1. D. Koutsoyiannis, A random walk on water, Hydrology and Earth System Sciences, 14, 585–601, doi:10.5194/hess-14-585-2010, 2010.

Our works that reference this work:

1. D. Koutsoyiannis, A. Christofides, A. Efstratiadis, G. G. Anagnostopoulos, and N. Mamassis, Scientific dialogue on climate: is it giving black eyes or opening closed eyes? Reply to “A black eye for the Hydrological Sciences Journal” by D. Huard, Hydrological Sciences Journal, 56 (7), 1334–1339, doi:10.1080/02626667.2011.610759, 2011.

Other works that reference this work (this list might be obsolete):

1. Ward, J. D., A. D. Werner, W. P. Nel, and S. Beecham, The influence of constrained fossil fuel emissions scenarios on climate and water resource projections, Hydrology and Earth System Sciences, 15, 1879-1893, 2011.