Quantitative approaches

The quest for numbers…

… and the problems it leads to

Why is it difficult?1. Debates on controversies over the concept and

very definition of environmental migration But similar controversies with regard to refugees

2. Intra-national movements

3. Confusion between the number of people living in affected regions and the number of migrants

Rooted in a deterministic perspective

4. Uncertainties about the impacts of climate change

5. Importance of the timeframe Are we talking about cumulative

migrations/displacements?

What do we have so far?

Annual estimates of people displaced by disasters (IDMC)

A few statistical analyses inferences Example: Feng, Krueger and Oppenheimer on

Mexico-US migration (PNAS 2010) And even fewer multi-level analyses

Example: Henry et al. on Burkina Faso (2004)

How to move forward? Set the right framework

Agree on the typology and definition

Re-scale predictions Is there a need for a global figure? Which level of warming?

Explore new methods

New methods Multi-level analysis

One of the most robust methods Combines different methods on different levels

Household surveys Time-series

Allows for the monitoring of migration trends over longer periods of time

Multi-variate models

Agent-based modeling

An exemple of multi-variate model (Ginnetti and Frank 2013)