# Regional Climate Change in Southeast Mexico-Yucatan Peninsula, Central America and the Caribbean
## 1 Introduction  
Recent data indicate that humanity releases 51 billion tons of greenhouse gases per year into the atmosphere [1], directly resulting in global warming and climate change. Climate change is considered to be the greatest threat of the 21 st century [2, 3]. It manifests itself in increases in the frequency and magnitude of extreme weather events, such as droughts and floods [4, 5], and its negative impacts on the natural, environmental, economic, and social spheres [6]. In addition, the differentiated effect of climate change occurs in tropical and arid areas [4], urban and rural areas, and in developing countries [3, 7, 8]. Mexico is characterized by a multi-diversity of climates and biomes. Due to its location and geographical and socioeconomic factors, the territory of Mexico is particularly affectedby hydrometeorological events, presenting a high vulnerability to the adverse effects associated with extreme weather events and climate change [8]. Precipitation in southern Mexico is driven by tropical circulation, tropical cyclones, orographic precipitation, easterly waves, the Mid-Summer Drought (MSD), and the Caribbean low-level jet (CLIJ), among other factors [9]. There are some changes in the climate already reported in this region. For instance, the temperature of the Usumacimta basin increased, and precipitation decreased during 1961-2013 [10] and 1965-1994 [11]. In [12], the authors report that the temperature is also increasing in the state of Tabasco, in southern Mexico. MSD [13,14] reaches its maximum in July and August. Annual precipitation in southern Mexico is approximately 2000 mm, and annual mean temperatures are between 20 \({}^{\circ}\)C and 35 \({}^{\circ}\)C. Furthermore, the great climate modulators (El Nino Southern Oscillation (ENSO); Pacific Decadal Oscillation (PDO); Atlantic Multidecadal Oscillation (AMO) and Low-Level Jet (LLJ)) effects are also present, such as high precipitation or severe drought events [3,7,13,14,15,16,17,18]. The Central America (CA) region is identified as a unique climate region and a key point of tropical climate change due to its location between two main water bodies: the Pacific Ocean and Caribbean Sea [19, 20, 21]. CA experiences the influence of both oceans in terms of precipitation from the meteorological systems, including trade winds, east waves, tropical cyclones, and the intertropical convergence zone [22], in addition to the intensity of the subtropical high-pressure system over the Caribbean Sea and of the Caribbean Low-Level Jet (CLIJ) [21]. In general, [23] point out that the prevailing climate in this region can be classified as dry tropical winter with very intense rains during the rainy season. However, the CA north regions facing the Caribbean Sea are wet almost all year, while the regions facing the Pacific Ocean have a dry season from December to May [21,24]. In [13], the authors argue that in CA, there is an increase in the minimum and maximum temperatures and related extreme events, such as heavy rains. In addition, [13] report that the larger region of CA is warming, there were no significant changes in the precipitation in the period of 1971-2000 compared to the 1961-2003 period. According to [20,25], observed changes to the climate, including increasing temperature and changing precipitation patterns, are expected to intensify hydrological extremes (floods and droughs) in the near future for this region. Caribbean island states have repeatedly emphasized the threats of climate change and their vulnerability to climate variations in key areas related to water and energy supplies and agriculture [26]. For the Caribbean region, temperature increases are also observed [27,28]. In its turn, precipitation has a slightly decreasing trend in some regions [27,29], and in other regions, precipitation is increasing [27,30].