The linkages between climatic stresses and shocks and migration, however are not linear. As Kniveton et al. (2009: 72) notes, international migration could increase or decrease as a response to such stimuli: “International migration increased with loss of harvest and livestock, but decreased following a severe earthquake in El Salvador (Halliday 2006); decreased in drought years in Burkina Faso (Henry et al. 2004) and Mali (Findley 1994); both increased and decreased with declining rainfall in Mexico (Munshi 2003; Kniveton et al. 2008).” In Sub-Saharan Africa deteriorating rainfall conditions tend to increase urban migration; in Mali, however, during the 1983-85 drought people affected could not afford to migrate to cities (Foresight 2011). Disaster-related migration is often short-term and involves short distances. For example, 88 per cent of migrant agricultural communities in Bangladesh were found to remain within two miles of their previous
residence following the erosion of land and loss of homes due to flooding (Zaman 1989). Similar trends were found on cyclone response too. Such rapid-onset disasters lead to temporary displacement to nearby areas as people lack resources to move farther, and many return and reconstruct their homes (Piguet 2011). Besides people prefer to stay with family and friends, linked to social networks (Barnet and Weber 2009), and continue to live in ways familiar to them (Perch-Nielson et al. 2008). However, it may be noted that migration is not always a primary response to a disaster, especially when emergency aid compensates for damage (Kniveton et al. 2009). Often seasonal and circular migration is an important livelihood option that helps communities gather resources from their destination while offsetting the resource pressure back home. Movement induced by climate change is likely to be short-term and occur internally over short distances, especially in low-income countries (Sward and Codjoe 2012; Gemenne 2011b). Often rural-rural migration is common within the poor groups that are vulnerable to climate change. Moving to cities often demands different skill sets, and more capital. This could be one more reason for people with less capital to get trapped in their original region, in environmentally vulnerable and degraded settings (Guzman et al. 2009; Foresight 2011). Migration opportunities may be severely limited for poor people in such places. The emerging picture is that internal migration often intensifies following major droughts or famines (Kniveton et al. 2008). Short, temporary migration induced by environmental stresses and shocks, often involve poor people. International migration is not a likely option for the poorest in general (Black et al. 2011a; Kniveton et al. 2008). As such internal migration is a far more widespread phenomenon than external migration. World figures show that there are 214 million international migrants and 740 million internal migrants (IOM 2011).