This is a continuation of a previous post, and this one will be even less intelligible unless you read that one first.

So, even though we rarely use the term, geoscientists have our metanarratives. Metanarrative is something of a perjorative for postmodern (pomo) critical social theorists, but just because because a metanarrative doesn’t really explain everything, even within its domain, doesn’t make it wrong, useless, or even hubris-y. As long we don’t make claims or insinuations, or have expectations, of a “theory of everything,” overarching theories or explanatory frameworks can be evaluated on their own merits or lack thereof—that is, whether a construct can be considered a metanarrative or not is independent of its utility and value.

At my job I am housed in a building occupied mostly by social science and humanities scholars, many of whom are postmodern, post-structuralist, “critical” social theory oriented. The “critical” is in quotes not to cast aspersions, but because these folks use the term somewhat differently than do scientists, for whom all well-conceived legitimate work is critical in the sense of skepticism, testability, and the potential for falsification.  Anyway, my office location ensures that I am exposed to a good deal of the concepts and jargon of that community.

One of those is metanarrative. According to the Sociology Index web site:

A lot of us in the geoscience business are concerned these days with interpreting ongoing and past, and predicting future, responses of landforms, soils, and ecosystems to climate change. As one of my interests is rivers, I have noted over the years that in a lot of the literature on paleohydrology the major changes, such as major influxes of sediment, seem to occur at climate transitions, rather than after climate changes or shifts have had a chance to settle in and exert their impacts for awhile.

A related issue is the relationship between precipitation, temperature, runoff, erosion, and vegetation. As climate changes both temperature and precipitation regimes change. And as every physical geography student knows, moisture availability is not just about precipitation, but the balance between precipitation and evapotranspiration (ET). So, if both temperature and precipitation are increasing (as is the case on average on much of the planet now), whether available moisture increases or decreases depends on the relative increases of precipitation and ET.  

Soil erosion on cropland.