Mesoamerican chronologyMesoamerican chronology divides the history of prehispanic Mesoamerica into several periods: the Paleo-Indian (first human habitation until 3500 BCE); the Archaic (before 2600 BCE), the Preclassic or Formative (2500 BCE – 250 CE), the Classic (250–900 CE), and the Postclassic (); as well as the post European contact Colonial Period (1521–1821), and Postcolonial, or the period after independence from Spain (1821–present). The periodisation of Mesoamerica by researchers is based on archaeological, ethnohistorical, and modern cultural anthropology research dating to the early twentieth century.
ReforestationReforestation (occasionally, reafforestation) is the natural or intentional restocking of existing forests and woodlands (forestation) that have been depleted, usually through deforestation but also after clearcutting. A debated issue in managed reforestation is whether the succeeding forest will have the same biodiversity as the original forest. If the forest is replaced with only one species of tree and all other vegetation is prevented from growing back, a monoculture forest similar to agricultural crops would be the result.
Climate modelNumerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the climate system to projections of future climate. Climate models may also be qualitative (i.e. not numerical) models and also narratives, largely descriptive, of possible futures.
Maya cityMaya cities were the centres of population of the pre-Columbian Maya civilization of Mesoamerica. They served the specialised roles of administration, commerce, manufacturing and religion that characterised ancient cities worldwide. Maya cities tended to be more dispersed than cities in other societies, even within Mesoamerica, as a result of adaptation to a lowland tropical environment that allowed food production amidst areas dedicated to other activities.
Maya warfareAlthough the Maya were once thought to have been peaceful, current theories emphasize the role of inter-polity warfare as a factor in the development and perpetuation of Maya society. The goals and motives of warfare in Maya culture are not thoroughly understood, but scholars have developed models for Maya warfare based on several lines of evidence, including fortified defenses around structure complexes, artistic and epigraphic depictions of war, and the presence of weapons such as obsidian blades and projectile points in the archaeological record.
ClimateClimate is the long-term weather pattern in a region, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation. In a broader sense, climate is the state of the components of the climate system, including the atmosphere, hydrosphere, cryosphere, lithosphere and biosphere and the interactions between them.
Pre-Columbian artPre-Columbian art refers to the visual arts of indigenous peoples of the Caribbean, North, Central, and South Americas from at least 13,000 BCE to the European conquests starting in the late 15th and early 16th centuries. The Pre-Columbian era continued for a time after these in many places, or had a transitional phase afterwards. Many types of perishable artifacts that were once very common, such as woven textiles, typically have not been preserved, but Precolumbian monumental sculpture, metalwork in gold, pottery, and painting on ceramics, walls, and rocks have survived more frequently.
Forest ecologyForest ecology is the scientific study of the interrelated patterns, processes, flora, fauna and ecosystems in forests. The management of forests is known as forestry, silviculture, and forest management. A forest ecosystem is a natural woodland unit consisting of all plants, animals, and micro-organisms (Biotic components) in that area functioning together with all of the non-living physical (abiotic) factors of the environment. Forests have an enormously important role to play in the global ecosystem.
General circulation modelA general circulation model (GCM) is a type of climate model. It employs a mathematical model of the general circulation of a planetary atmosphere or ocean. It uses the Navier–Stokes equations on a rotating sphere with thermodynamic terms for various energy sources (radiation, latent heat). These equations are the basis for computer programs used to simulate the Earth's atmosphere or oceans. Atmospheric and oceanic GCMs (AGCM and OGCM) are key components along with sea ice and land-surface components.
Climate actionClimate action (or climate change action) refers to a range of activities, mechanisms, policy instruments and so forth that aim to reduce the severity of human induced climate change and its impacts. "More climate action" is a central demand of the climate movement. Climate inaction is the absence of climate action. Examples for climate action include: Business action on climate change Climate change adaptation Climate change mitigation Climate finance Climate movement – actions by non-governmental organiz
