Climate Change Vulnerability Assessment in Jalisco: A Comprehensive Analysis

The changes in temperatures and precipitation estimated for the different climate change scenarios will have an impact on all sectors in the world, Mexico and Jalisco. Variations in temperature, precipitation, relative humidity, melting glaciers, expansion of water bodies due to thermal expansion and the rise in sea level in recent decades in the intertropical zone are evidence of the country's high vulnerability to climate change. Significant increases in temperature, decreases in precipitation and runoff will cause scarcity and pressure on water resources, health, agriculture, livestock, marine ecosystems, industry, biodiversity, urban development, energy, housing, mobility, economy, waste, among others.

Aims: The objective of this study is to present regional projections of temperature and precipitation in Jalisco, under the IPCC's AR6 climate change scenarios, improving the projections of the Oceanic-Atmospheric General Circulation Models and estimating the possible impacts of climate change in Jalisco.

Methodology: A total of 27 CLIMDEX climate change indices were calculated, using 197 stations distributed in the 125 municipalities of the State of Jalisco. For the regional modeling, the PRECIS (Providing Regional Climates for Impact Studies) model was used, developed by the Hadley Center of the United Kingdom, in a domain that covers the west of the Mexican Republic with a resolution of 25 km in the period 2020-2099.

Results: Regional models for Jalisco show temperature increase between 0.5 to 5°C, while % precipitation will range between -20.3 and 13.5% depending on the scenario and period of analysis. The increase in temperature will cause soil moisture deficits, water stress, sparse vegetation and semi-permanent meteorological drought. Under these scenarios, the entire country is expected to be subject to moderate to extremely severe droughts that will last and worsen between now and the end of the century. Regional modelling shows significant impacts on the water sector with low water availability; in the agricultural sector with a decline in the productivity of the state's crops, mainly affecting small landowners and subsistence farmers. As for livestock, the increase in temperatures will decrease the availability of water and feed; cattle will enter heat stress and increase respiratory and heart rate, which will decrease productivity and with the possible disappearance of livestock areas. In terms of biodiversity, it is estimated that between 20-30% of plant and animal species are at greater risk of migration and/or extinction due to temperature increase >3 ºC. The vulnerability of biodiversity will occur due to the weakening of ecosystems, forest fires, land use change and the decline of water resources. The energy sector will be affected by the increase in temperature, greater demand for energy, decrease in energy production, the main effects will be on its distribution. The health sector will be affected due to the presence of heat waves, heat stress and heat stroke; diseases due to high concentrations of pollutants, respiratory, cardio-vascular, vector-borne and contaminated water diseases, neurological and/or mental diseases, among others. Children, the elderly, and people with chronic and degenerative diseases will be the most vulnerable groups. All areas of the state will be impacted, although in a differentiated way, the lack of availability of water will occur throughout the state, agriculture and livestock in the area of Los Altos, floods and loss of biodiversity in coastal areas, the central area will concentrate most of the impacts due to the high population density.

Conclusion: it is estimated that Jalisco's vulnerability to climate change is high to very high in all sectors and in all regions of the State of Jalisco.