The impact of climate variability on agricultural employment in Mexico from 1980–2017

[1]. For example, Sultan et al. [2] demonstrated the negative effects of global warming on millet and sorghum crop yields in West Africa, and Moura da Silva et al. [3] documented the yield risks of soybean cultivation in Brazil. The impact of extreme events are not limited to develop- ing nations, but have also been widespread in developed regions such as Europe [4, 5], North America [6, 7], and Australia [8, 9]. This situation threatens the progress of global food secu- rity, as well as the livelihoods of people who depend directly on this activity [10]. Climate change, therefore, jeopardizes not only food production but also social structures. There are several examples of the cascading effects of climate variability in modern agricul- ture, and the livelihoods of people who depend on it. One such example is the ongoing conflict in Syria that began in 2011. The intensification of this conflict has been correlated with one of the worst droughts the country has faced. It is argued that the drought exacerbated the already existing water and agricultural insecurity, as it caused massive agricultural failures and increased livestock mortality [11]. Another example is sub-Saharan Africa; where it has been observed that dry precipitation anomalies reduce the number of violent events between armed actors; however, extremely dry conditions increase riots and violence against civilians [12]. Interestingly, these types of conflicts may result from an immediate response of the population to meteorological stress [12]. One last example is the impact of precipitation on children’s edu-

cation. Higher than normal rainfall has been found to correlate negatively with the educational attainment of children in Central America and the Caribbean; likely because children experi- ence poorer health and nutrition as a result of flooding and crop failure [13]. Thus, climate variability is still a key demographic driver for most modern societies. At the core of this link between climate variability and demographic patterns, is employ- ment in the agricultural sector [14]. Globally, most agricultural jobs depend on predictable rainfall, both terms of quantity and seasonality [15]; thus, significant deviations from regular climatic patterns can lead to the abandonment of these activities [16]. Several examples of this phenomenon exist in different parts of our planet. In Nigeria, reduced rainfall initially raises agricultural employment, as farming requires more labor in dry conditions; however, pro- tracted droughts significantly reduce agricultural jobs due to lower crop yields [17]. In the United States it has been shown that drier than usual weather conditions negatively impact the total wages paid to agricultural employment on crop-producing farms, and reduces net occu- pation in the primary sector [18]. A final example is Mexico, where it has been shown that storms can have significant negative associations with labor market outcomes because of reduced agricultural productivity [19]. Thus, there is theoretical evidence exposing the impact of climate extremes on employment. Mexico has been identified as one of the most vulnerable countries to climate change, par-

ticularly in terms of its agrarian structure [20]. During extreme dry years the country has expe- rienced decreases in rainfed agriculture production [21] and cattle populations [22]. An example of this was the 2011–2012 drought years in which cattle and goat populations declined by about 3% [23], and maize production decreased by 17%. In other words, Mexican agricul- ture is highly dependent on rainfall; years with good rainfall translate into high agricultural production (both crops and livestock products), and vice versa. The impacts of severe weather in Mexico are not limited to agricultural production but also have a profound effect on the livelihoods of farmers. Recent studies have reported that migration from Mexico to the U.S. increased as a consequence of decreased precipitation [24]. Other studies have observed that in a drought year, the probability of migrating to the U.S. increases [25]. The impact of dry conditions is not uniform across Mexico; droughts have a greater influence on emigration from rural areas in states with dry climates [26]. One of the most important demographic processes in Mexico is the change in agrarian employment. Throughout history, the primary sector has been considered a significant PLOS ONE Agrarian abandonment and extreme events PLOS ONE | https://doi.org/10.1371/journal.pone.0313891 February 10, 2025 2 / 22 and https://www.inegi.org.mx/programas/ene/ 2004/ (ENE). Funding: All authors are grateful for funding for the development of this research article. We gratefully acknowledge funding from the National Council of

Science and Technology (CONACyT) through grant CVU 1245336. We are also grateful for funding from the Program for Support of Research and Technological Innovation Projects (PAPIIT) through projects IA200722 and IA200420. Finally, we are grateful for funding from the University Program for Research on Climate Change (PINCC) through the project "Impacts of past and future drought on rainfed food production in Mexico". The sponsors or funders played no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: All the authors have declared that no competing interests exist.