Physics of Terrestrial Systems

Kurt Roth

Aims:

1. Understand the physics underlying transport of water and dissolved chemicals through porous media, in particular through soils and aquifers.

2. Formulate corresponding models, typically in terms of non-linear partial dierential equations and associated material properties.

3. Study their phenomenology based on results from numerical simulations.

Applications:

Typical classes of problems that require knowledge from this course (but not covered here in any depth):

• weather prediction and climate modeling: soil-atmosphere coupling

• water resources: groundwater recharge, relation between permafrost on Tibetan plateau and water availability in Eastern China

• food production: availability of water and nutrients, prevention of salinization

• groundwater quality: salinization (over-pumping leading to saltwater intrusion from the sea or from deeper layers), contamination (agrochemicals; waste deposits; mining; natural, e.g., As in Bangladesh), purification (river bank filtration)

• geo-engineering: water-harvest systems, sealing systems for waste deposits, regional climate modification (oasis effect),..., planet building (sustainable irrigation on Moon or Mars)

• engineering: construction of roads and railroads in permafrost regions; microfluidic, fuel cells, ....

Fig. 1: Heavy irrigation in North China plain. 70% of all the freshwater is consumed for irrigation of agricultural land to maintain food production. A careful management is required to prevent over-exploitation of the groundwater as well as soil salinization. Failure to handle one or both of these problems extinguished a number of ancient cultures.

Concept

The course equally aims at theoretical underpinnings and at experimental evidence of the flow and transport phenomena. The lecture (2 h/week) covers part of the Soil Physics Lecture Notes. Students are asked to read the material in advance such that the lecture can focus on the illustration and discussion of the concepts and on the development of the model formulation at the blackboard. The lecture is accompanied by exercises (1 h/week).

Prerequisites

This course belongs to the Masters curriculum in physics. It may also be of interest for students of mathematics with an interest in applications and for students of geosciences and geography with an inclination towards theory and modeling. Calculus and a basic understanding of differential equations is required.

Language

Depending on student's choice, the course language will be English or German. Lecture notes and all supporting materials are in English.