Calculating Drive-time Buffers and Territories with Sparse Road Network

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1 Calculating Drive-time Buffers and Territories with Sparse Road Network Ran Tao 1, Jean-Claude Thill 1, James Walsh 1 Daniel Strandow 2, Michael Findley 3 1 University of North Carolina at Charlotte 2 Uppsala University, Sweden 3 University of Texas at Austin 1

2 Overview Importance of modeling territorial control for understanding dynamics of civil wars Little good data on territorial control Our aim is to create a GIS approach to accurately calculate territorial control over time Introduce the steps in our approach Discuss resulting maps & applications of our method Limitations and future work 2

3 Why Territorial Control Matters Both cause and effect Cause: characteristics of territory mountainous terrain, presence of natural resource wealth influences objectives and strategies of warring parties Effect: degree of territorial control influences how warring parties decide to use force, for example against civilians (Kalyvas, 2006): Use indiscriminate force (gravity bombs, terrorism) in areas where warring party exercises least control Use little violence in areas where warring party exercise most control Measuring control will allow better testing of these hypotheses, and allow better understanding of how battlefield outcomes lead to terrorism, refugee flows, etc. 3

4 Innovations Mapping based on event data that identifies the outcomes of specific battles during civil wars Uses a service area approach in GIS to map how far control radiates from locations of battlefields Control is ordinal rather than dichotomous: Side A complete control Side A incomplete control Contested terrain Side B complete control Side B incomplete control Reference of figure1: Jennifer Hazen, What Rebels Want: Resources and Supply Networks in Wartime (Ithaca: Cornell University Press, 2013), p. 106) 4

5 In GIS: Territory ~ Service Area Center Locations 1. Events: Source data from Uppsala Conflict Data Program s Georeferenced Event Data (UCDP-GED) Info: time, location, warring parties, degree of control 2. Major cities: Gov. complete control 3. Military bases: Gov. complete control Direction: moving away Travel time: customizable 5

6 Difficulties Poor transport infrastructure Mobility of armed troops Off-road movement is also important 6

7 Solution: build a hybrid transport network Road & Rail Land Cover Slope 7

8 Build a hybrid transport network Steps: 1. Create hexagon grid cells 2. Connect center of hexagon cells as artificial road 3. Integrate road, railway, and artificial road as one road system 4. Assign speeds 8

9 Speed = Maximal Speed * Slope * River Land Cover Type Maximal Speed (km/h) Road 35 Railway 20 Water 0 Evergreen Needle Leaf Forest 5 Evergreen Broad Leaf Forest 5 Deciduous Needle Leaf Forest 5 Deciduous Broad Leaf Forest 5 Mixed Forests 5 Closed Shrublands 5 Open Shrublands 7.5 Woody Savannas 7.5 Savannas 10 Grasslands 10 Permanent Wetland 5 Croplands 7.5 Urban and Built-Up 10 Cropland/Vegetation Mosaic 10 Snow and Ice 5 Barren or Sparsely Vegetated 10 Slope (Degree) Difficulty Slope s Impact <5 Easy 100% 5-10 Moderate 50% Hard 20% Difficult 10% >40 No-go Situation. 0% Cross a river? if intersected, the impedance doubles Reference: Intelligence Preparation of the Battlefield Field Manual ( 9

10 Network analysis: delineate territories 10

11 Overlapping rules Gov. Gov. Incomplete Control Gov. Complete Control Rebel Gov. Contested Incomplete AreaControl Different years Later always updates former Same year Different groups: create new contested area Same group go with more unclear situation e.g. incomplete control > complete control 11

12 Result map 12

13 Result map of Liberia 13

14 Annual changes

15 Area of control With GIS tool we can also extract other information within the territories e.g. population, natural resources, etc. 15

16 Summary Advantages of our approach On-road and off-road movement Multiple degrees of control Limitations Based on media reports of battlefield events Coverage is uneven across conflicts Assumptions about movement are dependent on context Future work Use these data to answer questions about effect of territorial control on conflict, such as locations of indiscriminate violence and role of natural resources Develop a near-real time, semi-automated system of measuring territorial control based on open-source coding of event data and territorial control 16