Climate change in Mexico is expected to have widespread impacts: with significant decreases in precipitation and increases in temperatures. This will put pressure on the economy, people and the biodiversity of many parts of the country, which have largely arid or hot climates. Already climate change has impacted agriculture, [1] biodiversity, farmer livelihoods, and migration, [2] [3] as well as water, health, air pollution, traffic disruption from floods, and housing vulnerability to landslides. [4] [5]
Altered precipitation patterns and warming temperatures have led to economic insecurity in Mexico, particularly for smallholder farmers who grow Mexico's economically and culturally important crops: maize and coffee. Climate change impacts are especially severe in Mexico City, due to increases in air pollution. [6] [ clarification needed ] Ecological impacts of climate change within Mexico include reductions in landscape connectivity and shifting migratory patterns of animals. Furthermore, climate change in Mexico is tied to worldwide trade and economic processes which relate directly to global food security.[ clarification needed ]
The mean annual temperature has increased by 0.6 °C in Mexico since 1960. [7] [8] [ needs update ] Temperature is expected to increase in Mexico by 1.1–3.0 °C by 2060 and 1.3–4.8 °C by 2090. [8] As such, scientists, including the IPCC, have classified the entire Central American region as a “climate change hot-spot” [9] and “highly vulnerable” to climate change. [10] [11]
Climate change models, while highly variable, have projected an increase in the variation and intensity of precipitation (i.e. floods and droughts) for the climate of Mexico. The largest changes in precipitation are anticipated to occur during the summer months, especially in southern Mexico. [12] [13] Precipitation is expected to decrease by −3% to −15% by 2090 for the country as a whole. [14] [8] Regionally, precipitation changes may be anywhere between −60% and +8%. [14] [8]
Mountain cloud forests, especially in the Michoacán, act as dispersal corridors for many species that travel between habitats. [15] These forests are highly subject to human disturbances such as mining and deforestation. [15] This is important because the distribution of these forests is an integral factor of landscape connectivity. [15] As the distribution of these forests changes due to climate effects, landscape connectivity is also affected. [15] An evaluation of this property of connectivity of the mountain cloud forests of Michoacán was carried out by researchers in order to determine which areas would best benefit from greater conservation efforts. [15]
Mexico contains a significant portion of the world's biodiversity, making it essential that "biodiversity hot-spots" present within its borders are properly protected from the effects of climate change. [16] A large amount of land in Mexico is already designated as protected areas, as such, these conservation areas are refugia for a number of threatened species. [16] Researchers are investigating how protected ecosystems in Mexico will be affected by climate change, and to what degree. [16] Their research concluded that all 40 of the studied protected areas are expected to face warming temperatures while 30 will face decreased precipitation. [16] The researchers suggest that their study be used to determine which of the protected areas in Mexico would benefit most from greater conservation efforts. [16]
Warming temperatures and land-use change are contributing to the movement of butterfly distributions up the Sierra de Juárez mountain range in Oaxaca, Mexico. [17] In 2016, research was conducted to determine which butterfly species were moving either up or down the mountain range. [17] The researchers determined that more species were moving upward than were moving downward. [17] The researchers also concluded that, as a result of distribution changes, there was a greater abundance of generalist butterfly species in lowlands. [17]
Bat distributions and ranges in Mexico are expected to shift as a result of changes in climate and increased land-use change. [18] As an indicator species, bats can provide researchers useful information on the degree and extent of climate related species responses. [18] Researchers analyzed previous records of bat occurrence across Mexico and used the derived data to project how bat species may respond to land-use change and climate effects. [18] Results showed that habitat suitability for over half of 130 bat species is expected to decrease under current climate trends. [18] The results also revealed that land-use change had less of an effect on habitat suitability for bats than climate change. [18]
A significant number of mammals are endemic to Mexico, an abundance of those species being small mammals. [19] Many of these small mammals are known to inhabit tropical areas of Mexico, however, it is these tropical dry ecosystems that are highly subject to the effects of land-use change and climate change, making small mammals particularly vulnerable. [19] Researchers set up a 19-year study of small mammal populations in the Chamela-Cuixmala Biosphere Reserve located in Jalisco, Mexico. [19] This site was chosen by the researchers due to the occurrence of a significant amount of anthropogenic disturbance in the surrounding area. [19] The researchers concluded that functional diversity in this area was lower than expected, and, as such, greater conservation efforts should be encouraged in the region. [19]
In order to determine how conservation efforts should be implemented in order to best protect breeding bird communities, a study was conducted by Aaron D. Flesch. [20] This study of breeding bird communities in Mexico found that species were trending higher in altitude and towards the poles. [20] In order to collect his data, Flesch used techniques that had been used by previous researchers and conducted an observational survey to determine biodiversity values. [20] From the collected data and historical climate data, Flesch found that some lowland species moved north and others moved east to higher altitudes. [20]
In 2017, an estimated seven million people were employed in the agricultural sector in Mexico. [21] Climate change has caused many people in Mexico who depend on agriculture for employment to experience economic insecurity.
"Wheat production for Mexico is expected to decline by 12% under the future RCP 8.5 climate change scenario with additional losses of 7 to 18% because of O3 impact," according to a July 2019 article. [22] In the Yucatán Peninsula, the rise in temperature is affecting crop production. [1] Extreme heat can negatively affect crops by slowing down growth and increasing moisture loss in the soil. [23] Over the past 15 years until 2010, a Mayan village in Cancún, Tabi, experienced a 50-60% reduction in crop yield. Additionally, climate change is affecting rainfall patterns. Farmers are finding it more difficult to predict rainfall, which if predicted wrong can waste "an entire season's worth of seeds". [24]
Drying and warming trends are altering and shifting climatic zones and agricultural environments worldwide, [25] [26] and Mexico is no exception. [25] According to the World Bank, "agriculture [in Mexico] is highly vulnerable to weather extremes, in particular in the Northern parts of the country, where water scarcity is an issue, or the Southern parts of the country, where tropical storms cause extensive damage to crop[s]." [27] [8]
Exact predictions are difficult to make due to the complexity of the factors involved and the impacts will be highly region-specific; however, there is a general consensus that the productivity of crops and livestock will decline. [28] Scientists also expect that certain insect pests and plant pathogens will survive and reproduce more often due to warming temperatures and are likely to invade new regions. [29] Highland farmers and the rural poor are especially vulnerable to these climatic shifts. [25] Decreased precipitation will place higher burdens on irrigated agriculture, on which much of the country's exported, economically-important crops rely. [30] Conversely, more intense rainfall events will damage crop production. Higher temperatures are expected to increase evapotranspiration rates, leading to drying trends in soil moisture. [30]
Climate change threatens not only food and economic security in Mexico, but is also tied to much larger, global food systems. In 2017, the United States imported $13.3 billion of fruits and vegetables from Mexico. [21] Declining crop yields in Mexico due to climate change will ultimately impact global trade networks, national economies, and food security in countries that are, perhaps, geographically distant; yet through free-trade policies such as NAFTA and USMCA, have become highly dependent on Mexican agriculture.
Maize is of central importance to Mexican agriculture, occupying the largest cultivated area in the country. [25] It is a critical component of the diets and nutritional intake of both the urban and rural populations. A large number of smallholder farmers in Mexico depend on rain-fed maize for their livelihoods, leaving these farmers particularly vulnerable to temperature and precipitation fluxes from climate change. [25] Mexico's maize yields are expected to decline from 1555 to 1440 kg/ha by 2055. [31] An absolute decline of 883,200 t. in maize annual production is estimated to occur within this timeframe. [31] Maize is closely tied to Mexican identity, thus any decline in maize productivity and diversity will also have important socio-cultural and political consequences. [32] [8]
Mexico (Mesoamerica more generally) is the center of origin for maize. Mexico alone has 59 unique maize landraces recorded [33] and thousands of regionally adapted maize varieties. Maize diversity in Mexico continues to be maintained and managed by smallholder farmers who participate in traditional seed sharing networks. Maize landraces in Mexico are conserved in place, or in-situ, by farmers who continue to grow them in their fields. Commercial maize seed is planted on less than one-fourth of Mexico's 8 million hectares of arable land. [8] The majority of farmers in Mexico use, save, and exchange the seed of traditional maize landraces along with “creolized” (hybridized or cross-pollinated) commercial cultivars, which are typically planted in small (<5 ha) rain-fed fields. [8]
An estimated 18 percent of maize cultivation in Mexico takes place in the highlands, and maize agro-climates in the highland regions are most at risk from climate change. [25] Many scientists are concerned about the effects climate change poses on maize genetic diversity and the negative impacts that continued maize germplasm loss will have, not only on Mexican agriculture, but worldwide, as maize is the most widely grown crop in the world. [33] Bellon et al. (2011) discuss the need to strengthen and broaden traditional seed networks in Mexico to support farmers and the genetic integrity of maize in light of climate change; thus, extending the geographic ranges of seed networks to link farmers in the highlands, for example, with farmers in mid-altitude environments. [25]
In Mexico and Central America more broadly, some 8.5 million people rely on coffee production for their livelihoods. [13] Variable and extreme climatic events such as droughts, floods, and excessive heat is already impacting both the quality and overall production of coffee in Mexico. [10] In 2012, higher than average temperatures and high-altitude rains led to an outbreak of coffee leaf rust, affecting roughly 50 percent of the coffee crop in Central America. [13] This resulted in $500 million in crop damages to the region and caused many people in the region to lose their livelihoods. [13] Regional studies in Mexico have projected that coffee growing could be unviable by the end of the decade. [10]
Responses will need to occur both in the social and ecological realms and across multiple scales. Key strategies include crop diversification and the implementation of more resilient coffee production systems. Farmer education, access to information, health, and equity factors all play important roles in adaptation responses as well. [10] [13] Yet, there are also large-scale and global factors at play, such as international trade markets, which are often volatile, that are beyond farmers’ control. A handful of coffee companies, NGOs, and agencies have initiated training and education programs for Mexican farmers to better respond to climate change. [13]
Many Mexican smallholder farmers continue to depend on rain-fed agriculture for their subsistence and livelihoods. [30] Climate change is very closely tied to environmental justice in Mexico, given that poor smallholder farmers will likely carry the largest burden. [32] Farmers respond to climate change in varying ways: changing their agricultural practices, adjusting their livelihood strategies, or exiting agriculture altogether. [25]
There is evidence to suggest that declining agricultural conditions from climate change in Mexico directly relates to migration to the United States. [34] [10] For example, a direct relationship between declining crop yields in Mexico and migration was found. [34] Declines in agricultural productivity due to climate change might cause 1.4 to 6.7 million adult Mexicans to emigrate by the year 2080. [34]
In 2012, Mexico passed a comprehensive climate change bill, a first in the developing world, that has set a goal for the country to generate 35% of its energy from clean energy sources by 2024, and to cut emissions by 50% by 2050, from the level found in 2000. [36] [37] During the 2016 North American Leaders' Summit, the target of 50% of electricity generated from renewable sources by 2025 was announced. [38] Various climate mitigation efforts have been implemented throughout the country. Mexico has been considered a leader in climate mitigation and climate adaptation. [39] [40] [41] [42] [43]
The Paris agreement is a legally binding international agreement, its main goal is to limit global warming to below 1.5 degrees Celsius, compared to pre-industrial levels. [44] The Nationally Determined Contributions (NDC's) are the plans to fight climate change adapted for each country. [45] Every party in the agreement has different targets based on its own historical climate records and country's circumstances and all the targets for each country are stated in their NDC. [46]
The NDC target regarding México against climate change and greenhouse gas emissions under the Paris agreement are the following: [47]
Every country has different ways to achieve the established goals depending on his size, history and resources. In the case of México, the government has applied the following rules to support the NDC's climate change plan: [48]
Environmental degradation is the deterioration of the environment through depletion of resources such as quality of air, water and soil; the destruction of ecosystems; habitat destruction; the extinction of wildlife; and pollution. It is defined as any change or disturbance to the environment perceived to be deleterious or undesirable. Environmental degradation process amplify the impact of environmental issues leave lasting impacts on the environment.
A landrace is a domesticated, locally adapted, often traditional variety of a species of animal or plant that has developed over time, through adaptation to its natural and cultural environment of agriculture and pastoralism, and due to isolation from other populations of the species. Landraces are distinct from cultivars and from standard breeds.
Agricultural biodiversity or agrobiodiversity is a subset of general biodiversity pertaining to agriculture. It can be defined as "the variety and variability of animals, plants and micro-organisms at the genetic, species and ecosystem levels that sustain the ecosystem structures, functions and processes in and around production systems, and that provide food and non-food agricultural products.” It is managed by farmers, pastoralists, fishers and forest dwellers, agrobiodiversity provides stability, adaptability and resilience and constitutes a key element of the livelihood strategies of rural communities throughout the world. Agrobiodiversity is central to sustainable food systems and sustainable diets. The use of agricultural biodiversity can contribute to food security, nutrition security, and livelihood security, and it is critical for climate adaptation and climate mitigation.
Agroforestry is a land use management system in which combinations of trees are grown around or among crops or pasture. Agroforestry combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy, and sustainable land-use systems. Benefits include increasing farm profitability, reduced soil erosion, creating wildlife habitat, managing animal waste, increased biodiversity, improved soil structure, and carbon sequestration.
A smallholding or smallholder is a small farm operating under a small-scale agriculture model. Definitions vary widely for what constitutes a smallholder or small-scale farm, including factors such as size, food production technique or technology, involvement of family in labor and economic impact. Smallholdings are usually farms supporting a single family with a mixture of cash crops and subsistence farming. As a country becomes more affluent, smallholdings may not be self-sufficient, but may be valued for the rural lifestyle. As the sustainable food and local food movements grow in affluent countries, some of these smallholdings are gaining increased economic viability. There are an estimated 500 million smallholder farms in developing countries of the world alone, supporting almost two billion people.
Food biodiversity is defined as "the diversity of plants, animals and other organisms used for food, covering the genetic resources within species, between species and provided by ecosystems."
Shade-grown coffee is a form of the crop produced from coffee plants grown under a canopy of trees. A canopy of assorted types of shade trees is created to cultivate shade-grown coffee. Because it incorporates principles of natural ecology to promote natural ecological relationships, shade-grown coffee can be considered an offshoot of agricultural permaculture or agroforestry. The resulting coffee can be marketed as "shade-grown".
The climate of Mexico is very diverse. The Tropic of Cancer effectively divides the country into temperate and tropical zones. Land that is north of the twenty-fourth parallel experiences lower temperatures during the winter months. South of the twenty-fourth parallel, temperatures are fairly consistent all year round and vary solely as a function of elevation. The north of the country usually receives less precipitation than the south.
Agroecology is an applied science that involves the adaptation of ecological concepts to the structure, performance, and management of sustainable agroecosystems. In Latin America, agroecological practices have a long history and vary between regions but share three main approaches or levels: plot scale, farm scale, and food system scale. Agroecology in Latin American countries can be used as a tool for providing both ecological, economic, and social benefits to the communities that practice it, as well as maintaining high biodiversity and providing refuges for flora and fauna in these countries. Due to its broad scope and versatility, it is often referred to as "a science, a movement, a practice."
Crop diversity or crop biodiversity is the variety and variability of crops, plants used in agriculture, including their genetic and phenotypic characteristics. It is a subset of a specific element of agricultural biodiversity. Over the past 50 years, there has been a major decline in two components of crop diversity; genetic diversity within each crop and the number of species commonly grown.
Climate change is an important issue in Sri Lanka, and its effects threaten to impact both human and natural systems. Roughly 50 percent of its 22 million citizens live in low-lying coastal areas in the west, south, and south-west of the island, and are at risk of future sea level rise. Climate change also threatens the island's biodiversity, including its marine ecosystem and coastal coral reef environments. Sea-level rise due to climate change has the potential to affect the overall abundance of endemic species. Sri Lanka's coastal regions, such as the Northern Province and the Northern Western Province, are considered major hotspots and extremely vulnerable to climate change. These maritime provinces are the most densely populated. In addition to being a threat to Sri Lanka's biodiversity, climate change may cause disastrous consequences on various levels in such areas. Such consequences include: Affecting agricultural productivity, causing natural disasters like floods and droughts, increasing the spread of infectious illnesses, and finally undermining the living standards.
Climate change in Africa is an increasingly serious threat as Africa is among the most vulnerable continents to the effects of climate change. Some sources even classify Africa as "the most vulnerable continent on Earth". Climate change and climate variability will negatively impact agricultural production, food security, water security and ecosystem services. As a result, there will be severe consequences on lives and sustainable development in Africa.
The effects of climate change in Saskatchewan are now being observed in parts of the province. There is evidence of reduction of biomass in Saskatchewan's boreal forests that is linked by researchers to drought-related water stress stemming from global warming, most likely caused by greenhouse gas emissions. While studies, as early as 1988 have shown that climate change will affect agriculture, whether the effects can be mitigated through adaptations of cultivars, or crops, is less clear. Resiliency of ecosystems may decline with large changes in temperature. The provincial government has responded to the threat of climate change by introducing a plan to reduce carbon emissions, "The Saskatchewan Energy and Climate Change Plan", in June 2007.
There are numerous effects of climate change on agriculture, many of which are making it harder for agricultural activities to provide global food security. Rising temperatures and changing weather patterns often result in lower crop yields due to water scarcity caused by drought, heat waves and flooding. These effects of climate change can also increase the currently-rare risk of several regions suffering simultaneous crop failures, which would have significant consequences for the global food supply. Many pests and plant diseases are also expected to either become more prevalent or to spread to new regions. The world's livestock are also expected to be affected by many of the same issues, from greater heat stress to animal feed shortfalls and the spread of parasites and vector-borne diseases.
Climate change in Tanzania is affecting the natural environment and residents of Tanzania. Temperatures in Tanzania are rising with a higher likelihood of intense rainfall events and of dry spells.
Climate change and agriculture are complexly related processes. In the United States, agriculture is the second largest emitter of greenhouse gases (GHG), behind the energy sector. Direct GHG emissions from the agricultural sector account for 8.4% of total U.S. emissions, but the loss of soil organic carbon through soil erosion indirectly contributes to emissions as well. While agriculture plays a role in propelling climate change, it is also affected by the direct and secondary consequences of climate change. USDA research indicates that these climatic changes will lead to a decline in yield and nutrient density in key crops, as well as decreased livestock productivity. Climate change poses unprecedented challenges to U.S. agriculture due to the sensitivity of agricultural productivity and costs to changing climate conditions. Rural communities dependent on agriculture are particularly vulnerable to climate change threats.
Climate change impacts are occurring in Zimbabwe, even though the country's contribution to greenhouse gas emissions is very minimal.
Climate change is the consequence of long-term alterations in the Earth's climate caused by the emission of greenhouse gases such as carbon dioxide (CO2) and methane (CH4). These gases can trap heat in the atmosphere, resulting in global warming and a heightened temperature on our planet. The activities carried out by humans, such as the utilization of fossil fuels, along with large-scale commercial agriculture and deforestation, are accountable for the release of these greenhouse gases. The escalating temperatures and escalating extreme heat conditions, uncertain and progressively unpredictable precipitation, and extreme weather provoke new challenges and exacerbate existing ones.
Lesotho is a country in southern Africa that is already experiencing the negative effects of climate change, including increased frequency of extreme weather, such as droughts, increased rates of soil erosion and desertification, and reduced soil fertility. Lesotho is a landlocked country that is particularly vulnerable to the negative impacts of climate variability and changes in water and food security, as well as adverse conditions to health, human settlements, and the energy sector.
Climate change effects on tropical regions includes changes in marine ecosystems, human livelihoods, biodiversity, degradation of tropical rainforests and effects the environmental stability in these areas. Climate change is characterized by alterations in temperature, precipitation patterns, and extreme weather events. Tropical areas, located between the Tropic of Cancer and the Tropic of Capricorn, are known for their warm temperatures, high biodiversity, and distinct ecosystems, including rainforests, coral reefs, and mangroves.