The document provides guidance for marking an essay about how and why glaciers move. It should explain the basic description and reasons for how glaciers move, addressing both cold-based and warm-based glaciers. Specifically, it mentions that cold-based glaciers move through internal deformation, laminar flow, and creep, while warm-based glaciers additionally move through basal sliding caused by regelation or creep. The essay should also explain the reasons for glacier movement, including mass, slope, mass balance, water at the base for warm-based glaciers, and gravity.

1. Mark your essay using the criteria below Explain how and why Glaciers move (15 marks) Explain involves a basic description plus reasons How and why both need addressing Expect reference to cold and warm based glaciers and comparisons between the 2. Why – Mass, slope, mass balance, water at the base (warm based only), gravity How – a) cold based – internal deformation (ice crystal movement) - Laminar flow (in layers) - Creep or plastic deformation b) Warm based – the above plus basal sliding by regelation (involves melting) or creep (plastic deformation) Could reference extending and compressing flow.

2. Objectives To understand how food supply can be considered to be Geography To gain an insight into the issues behind this unit Food Supply Issues

3. The syllabus Go through the syllabus and highlight all of the ideas you either: Know something about Are clueless about!

4. Short presentations Look at the resources on various food issues on my website. Take one of the resources each and answer the questions at the bottom of the page. You will have to present these ideas to the rest of the group.

5. Why are Food Supply Issues Geography?

6. Homework Read the other articles and images. First 2 reading sheets