According to a recent report by the World Bank, in South Asia, internal climate migrants could number over 40 million, 1.8% of the region’s total population. Climate migrants are projected to increase by a factor of six between 2020 and 2050, and the share of climate migrants in all internal migrants could reach as high as 25%.
Vietnam is one of the countries that will be highly affected by climate change in the years to come. The impact of climate variations is greatly enhanced by the fact that many Vietnamese households have climate-sensitive livelihoods. Despite its ongoing reduction over the last decades, the share of employment in agriculture on total employment is still high, around 44% in 2015 and agriculture still accounts for a significant part of the gross domestic product (GDP), around 20% in 2015. Vietnam is the fifth largest rice producer in the world and rice remains the staple food from which people obtain 51.7% of total calories and 40% of daily protein intake.
In light of these considerations, we investigated the relationship between climate and migration in rural households in Vietnam. The stream of literature relating these two phenomena is quite lively: the main hypothesis is that climate variations may dramatically affect the livelihood of individuals, thus, leaving them with no other choice but to migrate. We claim that climate change affects rice production, the main crop in Vietnam, and in turn, this modifies the set of economic opportunities, by increasing the cost of rice for consumers and therefore reducing their real income, reducing production for small landowners that see a fall in their income and possibly higher expenditure in fertilizers and irrigation to cope with reduced output and lower labour demand for workers involved in rice production, which leads to unemployment and lower wages. All these occurrences may lead to migration.
To this end, it is crucial to choose the most appropriate measure of climatic variation. Among social scientists, climate change is frequently approximated using average rainfall and temperature levels. However, drawing insights from natural science literature, the use of the average temperature may overshadow the effect that temperatures have on the growth of the main crop cultivated in a country. We use exogenous deviations in monthly minimum temperatures in the growing season as an instrument of rice production. In our analysis, we also include some controls for the specific socio-economic conditions coming from Vietnam Access to Resources Household Survey (VAHRS), a household survey held biannually from 2008 to 2016. We find that the rise of the minimum temperature during June, the core month of the growing season, does cause a reduction in rice production which, in turn, positively impacts people’s propensity to migrate.
It is noteworthy that our empirical analysis has been made possible thanks to the combination of the VARHS household dataset with CRU TS4.01 by the Climatic Research Unit at the University of East Anglia, which reports monthly time series of rainfall, minimum, mean and maximum temperature from 1901 to 2016 at 0.5 x 0.5‐degree grid. In particular, the main effort in constructing our dataset was the association of the observed households with the minimum temperature observed in the community where they were located.
Our study has two important implications for the development of Vietnamese rural households in the face of climate change. Firstly, it sheds light on the link between climate variations, agriculture production, and migration allowing the policymakers to fully understand how this phenomenon may impact people’s lives and to predict future population movements. Furthermore, this study also discloses some consequences of the excessive dependence of Vietnamese households on rice crops: households that are largely dependent on rice revenues are deemed to be severely affected by variations in the temperatures. This finding encourages the adoption of alternative crops that may be more resistant to climate variations, as well as the introduction of ad hoc policies to support the most climate-sensitive households.
The views and opinions expressed in this article are those of the author and do not necessarily reflect the views of Vision of Humanity.