Climatology and vulnerability to climate change in the “Altos de Jalisco” region, Mexico

The State of Jalisco has high levels of vulnerability to climate change, so it is necessary to identify the areas that present the highest risk. At present, it is important to have information to design and implement measures that reduce the effects of climate change on water resources. In Jalisco, the “Altos de Jalisco” and North regions are very vulnerable as they show a current and future water defi cit. The objective of this study is to expose the conditions of vulnerability of water resources in the “Altos de Jalisco”, an area of great economic importance for Jalisco and Mexico. The intention is to show the climatic conditions, the changes experienced by climate change through R-Climdex indicators and projections of future scenarios of temperature, humidity and precipitation using PRECIS, to fi nally expose the vulnerability of the water resource in the region. The results show conditions that coincide with the IPCC reports regarding global estimates of water availability; by the middle of this century, a 10-30% decrease in fresh water is estimated in the dry tropical areas (Mexico and Jalisco) that are already suffering from water stress. It is likely that as the century progresses, an increase in temperature and decrease in relative humidity and intensity of rainfall, and the consequent increase in the extent of areas affected by drought. Likewise, a decrease in water reserves is expected, which would reduce the availability of water in the region as we approach the end of the century. Introduction It is well known that from the end of the 19th century (industrial revolution) the temperature of the earth has increased, a phenomenon associated with the increase in greenhouse gases (carbon dioxide, methane, nitrous oxide, ozone, chlorofl uorocarbons, among others). The fi fth assessment report of the Intergovernmental Panel on Climate Change estimated a warming of 0.85 ± 0.20 °C, during the period 1880-2012, for which have occurred independently several sets of data [1]. In the case of Mexico, the average maximum and minimum temperatures have increased by about 0.3 °C per decade during the period 1971-2000, for the country as a whole [2]. Regional studies on changes in temperature for China, Japan, Korean Peninsula, the Mediterranean region and Europe show consistent patterns with a general warming. The last decade of the last century and the fi rst of this century have been the warmest years ever recorded. The phenomenon has been global in nature, although warming trends do not show a great spatial and temporal variability [3]. Most of the climate change projection studies have been carried out using average temperature records, without taking into account extreme temperatures. Since temperature is not only a component of climate change but also of climate variability, it is important to consider extreme temperatures both in the shortand long-term projections and at global and regional scales. The impacts on human comfort are related to extreme temperatures, especially those that exceed the daily tolerance levels for each of the different regions of the planet; another important factor is the frequency of these extreme events and their impact on water resources [4-7]. In addition to the impacts on comfort and human health, the impact on water resources is of paramount importance since they have implications on socioeconomic conditions, in the development of certain activities such as agriculture, livestock, forestry, energy generation, the development of industrial centers among others. Therefore, today it is of great relevance to carry out regional studies of climate change to evaluate the impacts in each particular region and not only to use global scale models [8-17]. 002 https://www.peertechzpublications.com/journals/annals-of-environmental-science-and-toxicology Citation: Ramírez-Sánchez HU, Fajardo-Montiel AL, García Guadalupe ME (2021) Climatology and vulnerability to climate change in the “Altos de Jalisco” region, Mexico. Ann Environ Sci Toxicol 5(1): 001-011. DOI: https://dx.doi.org/10.17352/aest.000029 Thanks to the development of supercomputing and progress in the understanding of the physical and chemical processes of the climate system and the development of regional modeling, more reliable regional projections of climate change can now be developed. However, there are social factors in each region (for example, the variation in population, economic development and the use of technology in each region, knowledge of the environment, the quantity and quality of meteorological and climatic data, among others, both current and future), which in many cases limit the effi ciency of these regional models and cause greater uncertainty in climate projection modeling [1821]. Hence, global climate scenarios have been developed and their possible consequences such as scenarios B1: 600 ppm, A1T: 700 ppm, B2: 800 ppm, A1B: 850 ppm, A2: 1250 ppm, A1FI: 1550 ppm [22] of greenhouse gases and RCP2.6, RCP4.5, RCP 6.0 and RCP 8.5 [23]; that have to do with radiative forcing. With these scenarios and with the help of Regional Models such as PRECIS (Providing Regional Climates for Impact Studies), it is possible to make regional approximations of future conditions with adequate data. In the same way, changes that have already occurred can be evaluated using past data to assess regional changes and their current and future implications through tools such as RClimdex that obtains indicators of climate change that have already occurred in the recent past. The changes in temperature, relative humidity and rainfall in the state of Jalisco indicated by the general atmosphereocean circulation models show an impact of climate change as a result of the increase in greenhouse gases [2]. There have been efforts on a global/regional scale to determine the nature of extreme changes in other regions of the world, however, there is no certainty of such changes with regional details in this region of Mexico [18-21]. This study seeks to demonstrate the changes that have already occurred and future projections of temperature, humidity, precipitation, among other meteorological variables under climate change scenarios towards the end of the 21st century, and assess the vulnerability of the water resource through regional climate models for the “Altos de Jalisco” region (Figure 1). Material and methods In Mexico, the institution in charge of measuring and collecting meteorological data is the National Meteorological Service (SMN acronym in Spanish), which is a dependency of the National Water Commission (CNA acronym in Spanish), which in turn belongs to the Secretary of the Environment and Natural Resources (SEMARNAT acronym in Spanish). In the particular case of the state of Jalisco, there is a network of 208 stations distributed in 125 municipalities. Of these, Figure 1: Location of the Altos Norte region in the state of Jalisco, Mexico. 003 https://www.peertechzpublications.com/journals/annals-of-environmental-science-and-toxicology Citation: Ramírez-Sánchez HU, Fajardo-Montiel AL, García Guadalupe ME (2021) Climatology and vulnerability to climate change in the “Altos de Jalisco” region, Mexico. Ann Environ Sci Toxicol 5(1): 001-011. DOI: https://dx.doi.org/10.17352/aest.000029 only 48 belong to the Altos region (20 municipalities), from these stations the meteorological data were obtained during the periods 1971-2000 and 1981-2010 [24]. Before being used, said data was subjected to a validation of the same through tools provided by the RClimdex Software as a prerequisite to the calculation of the climate change indices, since any outlier or erroneous value could signifi cantly alter the trends of each of the indexes evaluated. Thanks to this validation, outlier extreme values, lack of homogeneity and missing values were identifi ed in the data series [25]. The mission of the Commission of Experts in Climatology (ET-CCDMI) of the World Meteorological Organization (WMO) is to assess the evolution of climate change indices. Thus, the WMO developed indexes of climatic change important for a global analysis through the regional evaluation of the changes in certain meteorological parameters [26]. Said indices were evaluated using the RClimdex software in each station to evaluate trends and these were compared with PRECIS simulations during the same period [25]. The meteorological data from the baseline (1971-2000) were used to evaluate the ability of the model to represent regional climatic characteristics by comparing the models with the in situ data in each of the stations in the state of Jalisco. This comparison made it possible to evaluate and eliminate possible biases due to differences in special density between the observation and the model representations. The PRECIS climatological data is extracted for the coordinates of the respective station where actual observation data is available. Thus, through this methodology, the trends were calculated for each station in time series for indices as important as temperatures, relative humidity and precipitation, among other climatological variables. For the generation of PRECIS simulations of scenarios of the recent past period (1971-2000) and future scenarios of the period 2000-2100, the SRES (Special Reports on Emission Scenarios) A2 and A1B scenarios were used, both characterized by the focused regional development but with priority to economic issues in the fi rst and environmental issues in the second. The regional PRECIS model was confi gured for the geographic domain comprised between -101 ° 28 ° W to -105 ° 42 ° W of west longitude and 18 ° 55 ‘° N to 22 ° 45’ ° N of north latitude with a horizontal resolution of 0.22 ° x 0.22 °. Results Climatology The region “Altos de Jalisco” is characterized by its semidry and semi-warm dry and temperate climate. The average temperature is 18 °C, with extremes of 15 -21 °C (Figure 2). The average minimum is 8 °C, ranging between 6-13 °C (Figure 3); and the maximum average is 27 °C, which oscillates between 23-30 °C (Figure 4). The average relative humidity is 50-53% with extremes of 39-65% (Figure 5). The predominant winds are northwest and southeast in direction with variable speeds up to 60 km/h. The mean precipitation is 683 mm, with ranges from 480 to 902 mm (Figure 6). The average evaporation of the region is 1907 mm with extremes of 1458 to 2195 mm (Figure 7). The average number of days with rainfall is 68 with values between 49 and 91 days. The average number of days with fog is 10, ranging from 0 to 73 days. The average number of days with hail is 1, located between 0 and 3 days. On the other hand, the number of days with thunderstorms was 5, with oscillations between 0 and 31 (Figure 8). The total number of days with 17.6 17.8 19.8 15.9 20.8 17.5 17.6 18.2 17.0 17.9 17.2 15.5 15.3 18.0 17.7 18.1 18.4 17.5 17.5 17.1 17.3 17.8 17.3 17.0 18.0 17.7 16.8 16.8 19.5 17.8 18.2 17.1 15.3 17.9 17.8 17.7 18.4 20.4 17.4 18.9 20.4 17.0 18.0 17.7 20.8


Introduction
It is well known that from the end of the 19th century (industrial revolution) the temperature of the earth has increased, a phenomenon associated with the increase in greenhouse gases (carbon dioxide, methane, nitrous oxide, ozone, chlorofl uorocarbons, among others). The fi fth assessment report of the Intergovernmental Panel on Climate Change estimated a warming of 0.85 ± 0.20 °C, during the period 1880-2012, for which have occurred independently several sets of data [1]. In the case of Mexico, the average maximum and minimum temperatures have increased by about 0.3 °C per decade during the period 1971-2000, for the country as a whole [2].
Regional studies on changes in temperature for China, Japan, Korean Peninsula, the Mediterranean region and Europe show consistent patterns with a general warming. The last decade of the last century and the fi rst of this century have been the warmest years ever recorded. The phenomenon has been global in nature, although warming trends do not show a great spatial and temporal variability [3].
Most of the climate change projection studies have been carried out using average temperature records, without taking into account extreme temperatures. Since temperature is not only a component of climate change but also of climate variability, it is important to consider extreme temperatures both in the short-and long-term projections and at global and regional scales. The impacts on human comfort are related to extreme temperatures, especially those that exceed the daily tolerance levels for each of the different regions of the planet; another important factor is the frequency of these extreme events and their impact on water resources [4][5][6][7].
In addition to the impacts on comfort and human health, the impact on water resources is of paramount importance since they have implications on socioeconomic conditions, in the development of certain activities such as agriculture, livestock, forestry, energy generation, the development of industrial centers among others. Therefore, today it is of great relevance to carry out regional studies of climate change to evaluate the impacts in each particular region and not only to use global scale models [8][9][10][11][12][13][14][15][16][17].
Citation: Ramírez-Sánchez HU, Fajardo-Montiel AL, García Guadalupe ME (2021) Climatology and vulnerability to climate change in the "Altos de Jalisco" region, Mexico. Ann Environ Sci Toxicol 5(1): 001-011. DOI: https://dx.doi.org/10.17352/aest.000029 Thanks to the development of supercomputing and progress in the understanding of the physical and chemical processes of the climate system and the development of regional modeling, more reliable regional projections of climate change can now be developed. However, there are social factors in each region (for example, the variation in population, economic development and the use of technology in each region, knowledge of the environment, the quantity and quality of meteorological and climatic data, among others, both current and future), which in many cases limit the effi ciency of these regional models and cause greater uncertainty in climate projection modeling [18][19][20][21]. Hence, global climate scenarios have been developed and their possible consequences such as scenarios B1: 600 ppm, A1T: 700 ppm, B2: 800 ppm, A1B: 850 ppm, A2: 1250 ppm, A1FI: 1550 ppm [22] of greenhouse gases and RCP2.6, RCP4.5, RCP 6.0 and RCP 8.5 [23]; that have to do with radiative forcing. With these scenarios and with the help of Regional Models such as PRECIS (Providing Regional Climates for Impact Studies), it is possible to make regional approximations of future conditions with adequate data. In the same way, changes that have already occurred can be evaluated using past data to assess regional changes and their current and future implications through tools such as RClimdex that obtains indicators of climate change that have already occurred in the recent past.
The changes in temperature, relative humidity and rainfall in the state of Jalisco indicated by the general atmosphereocean circulation models show an impact of climate change as a result of the increase in greenhouse gases [2].
There have been efforts on a global/regional scale to determine the nature of extreme changes in other regions of the world, however, there is no certainty of such changes with regional details in this region of Mexico [18][19][20][21].
This study seeks to demonstrate the changes that have already occurred and future projections of temperature, humidity, precipitation, among other meteorological variables under climate change scenarios towards the end of the 21st century, and assess the vulnerability of the water resource through regional climate models for the "Altos de Jalisco" region ( Figure 1).

Material and methods
In Mexico, the institution in charge of measuring and collecting meteorological data is the National Meteorological Service (SMN acronym in Spanish), which is a dependency of the National Water Commission (CNA acronym in Spanish), which in turn belongs to the Secretary of the Environment and Natural Resources (SEMARNAT acronym in Spanish). In the particular case of the state of Jalisco, there is a network of 208 stations distributed in 125 municipalities. Of these, only 48 belong to the Altos region (20 municipalities), from these stations the meteorological data were obtained during the periods 1971-2000 and 1981-2010 [24]. Before being used, said data was subjected to a validation of the same through tools provided by the RClimdex Software as a prerequisite to the calculation of the climate change indices, since any outlier or erroneous value could signifi cantly alter the trends of each of the indexes evaluated. Thanks to this validation, outlier extreme values, lack of homogeneity and missing values were identifi ed in the data series [25].
The mission of the Commission of Experts in Climatology (ET-CCDMI) of the World Meteorological Organization (WMO) is to assess the evolution of climate change indices. Thus, the WMO developed indexes of climatic change important for a global analysis through the regional evaluation of the changes in certain meteorological parameters [26]. Said indices were evaluated using the RClimdex software in each station to evaluate trends and these were compared with PRECIS simulations during the same period [25]. The meteorological data from the baseline  were used to evaluate the ability of the model to represent regional climatic characteristics

Climatology
The region "Altos de Jalisco" is characterized by its semi-  frost is 24 with variations from 5 to 50. The average daytime temperature oscillation is 9 ° C, with a range between 6-11 ° C (Figures 2-8).
An analysis of the climates was carried out in the North and South high altitude regions, obtaining the following results:   Relative humidity (%)

Climate indicators RClimdex
For the calculation of the indicators of climate change, a database was constructed according to the climatological norm obtained from the site of the National Meteorological Service (NMS) of the National Water Commission (CONAGUA) to use the records of daily maximum and minimum temperatures as well as the amount during daily precipitation of the period 1982 to 2003.
A text fi le was constructed with the data ordered in columns by: year, month, day, precipitation (mm), maximum temperature (Celsius) and minimum temperature. Prior to the execution of RClimdex, a quality control (QC) of the data was performed. Finally with this data the RClimDex was executed.
The municipality of Lagos de Moreno presented the following indices of climate change: decrease in average days with frost from 1 to 6 days, variation from -50 to 140 in the average of summer days, variation from -0.8 to 0.3 days in the average of tropical nights, decrease between 0.2 and 3 days in the duration of the growing season, the maximum monthly value of maximum daily temperature increased by 3 °C, while the maximum monthly value of daily minimum temperature ranged from -2 to 0.5 °C, the minimum monthly value of daily maximum temperature decreased from 0.5 to 4 °C and the minimum monthly value of daily minimum temperature ranged from -1.5 to 2.2 °C. The average monthly difference ranged from -1.5 to 1.2 °C, the monthly maximum precipitation in 1 day increased from 2 to 10 mm, the monthly maximum precipitation in 5 consecutive days increased from 5 to 24 mm, the total annual precipitation divided by the number of wet days in a year increased to 2.7 mm / day, the number of days in a year where PRCP≥10mm ranged from -4 to 26mm, the number of days in a year where PRCP≥20mm ranged from -2.5 to 1 days, the maximum number of consecutive days with RR <1mm increase between 15 and 52 days, the maximum number of consecutive days with RR≥1mm ranged from -2 to 0.5 days, the total annual rainfall at which RR> 95th percentile oscillated between -100 and 45 mm, total annual rainfall in which RR> 99th percentile increased between 30 and 75 days and total annual rainfall on wet days (RR> = 1mm) increase between -50 and 50 mm. 1. Analyzing Figure 9 concludes the following:The trend of air temperature in Altos de Jalisco is growing with an increase by the end of study period of nearly 5 ° C.

The relative humidity is showing a reduction of about
5% by the end of study period.

The Intensity of Precipitation graph exhibits a downward
trend. The soil temperature demonstrates an increase similar to that of the air temperature graph with an increase at the end of the study period of more than 5 ºC.
Analyzing Figure 10, we conclude the following 1. The trend of air temperature in Altos de Jalisco is also growing with an increase by the end of study period by about 5.5 ° C, higher than that found for period of the rainy season.
2. The relative humidity shows a strong tendency to decrease, decreasing by about 11% by the end of study period; this is also much higher than what was projected for the rainy months. 4. The soil temperature tends to increase and the trend is similar to that of the air temperature with an increase at the end of the study period of analysis to a little more than 5 °C.

Discussion
The results suggest that the Altos de Jalisco region is exposed to strong increases in temperature, decreased rainfall and relative humidity and therefore a high risk of drought due to climate change. The combination of climate change and strong population growth is very likely to further exacerbate water scarcity. This situation begins to represent social unrest due to the fact that the basic needs of food, water for the population and development of all productive activities are no longer met. Therefore, climate change can become an indirect factor of social instability in the region. The climatic variables temperature and precipitation are the ones that are having the most impact on the availability of water, the increase in droughts, the impacts on agriculture and livestock, which are the main economic activities in the region.
As in other parts of the world, a signifi cant warming trend has been evidenced in recent decades, more pronounced in the summer and mainly with respect to minimum temperatures [27]. This is accompanied by increases in hot nights, hot days, and heat waves; reduction of cold waves among others [28].
Average precipitation during the rainy season has decreased in recent decades; as well as the rainfall during the wet season and that translates into a severe winter drought. The presence of some wet years is attributed more to climatic variability [27,29]. With regard to heavy rain events, most do not show signifi cant trends, while a general increase in the frequency of droughts is more common. The foregoing coincides with that evidenced in regions such as the Mediterranean basin where the impact of water resources is expected [33], in North Africa [34], southern Mediterranean [35]. In addition to decreases in water supply, several studies project a sharp increase in water demand due to population growth and economic development, indicating increased water stress in the future [36]. Climate model simulations converge towards a decrease in precipitation in summer and, to a lesser extent, in winter, which is responsible for the decrease in surface runoff and groundwater recharge. As a consequence of the decrease in surface runoff, a signifi cant Citation: Ramírez-Sánchez HU, Fajardo-Montiel AL, García Guadalupe ME (2021) Climatology and vulnerability to climate change in the "Altos de Jalisco" region, Mexico. Ann Environ Sci Toxicol 5(1): 001-011. DOI: https://dx.doi.org/10.17352/aest.000029 decrease in the supply of water to dams, reservoirs and low groundwater recharge is expected, which are used mainly for irrigation. Several studies in other regions of the world show that in many cases the decrease in groundwater recharge is the result of the reduction of surface runoff [37,38]; since in semi-arid environments, the targeted infi ltration of rivers is the main groundwater recharge process. It has been reported that the drop in groundwater levels due to overexploitation and degradation of water quality in aquifers. The main cause in Los Altos is the intense pumping of groundwater in agricultural activities, together with the demand from urban areas with high population densities. This shows that at the current rate of extraction, groundwater cannot be considered a long-term resource, given the greater variability of rainfall due to climate change. Thus, based on the foregoing, this region was identifi ed together with the northern region of the state of Jalisco as one of the regions with the greatest vulnerability to the decrease in surface and groundwater resources.

Conclusion
As predicted by the IPCC (2007) for global estimates of water availability by the middle of the century, a 10-30% decline in freshwater is forecast in dry, tropical areas (Mexico and the state of Jalisco). Some areas are already experiencing water stress; western Mexico is defi cient in surface and groundwater. As is known, the increasing water demands are: for irrigation to the South Coast region with demand of more than 800 million m 3 /a, for livestock in the Altos Norte Region with needs of more than 100 million m 3 /a, the Guadalajara metropolitan area with the highest demand for water for human settlements with over 100 million m 3 /a which is not satisfi ed with water available in the Central Region, which causes water demand from other regions such as Ciénega and Altos Sur. As the century advances, the demands will be increasing, which will lead to greater water stress in the Altos Region and the North Coast, while the largest groundwater defi cits will be presented in the Central Region, Altos Norte and Ciénega. It is likely that as the century progresses, with the increase in temperature and decrease in relative humidity and precipitation intensity, the amount of drought-affected areas will increase. Likewise, a decrease in the reserves of stored water is anticipated, which would reduce the availability of water as we approach the end of the century.