Effects of climate change in the context of "Climate warming"

Climate change and cities are deeply connected. Cities are one of the greatest contributors and likely best opportunities for addressing climate change. Cities are also one of the most vulnerable parts of the human society to the effects of climate change, and likely one of the most important solutions for reducing the environmental impact of humans. The UN projects that 68% of the world population will live in urban areas by 2050. In the year 2016, 31 mega-cities reported having at least 10 million in their population, 8 of which surpassed 20 million people. However, secondary cities - small to medium size cities (500,000 to 1 million) are rapidly increasing in number and are some of the fastest growing urbanizing areas in the world further contributing to climate change impacts. Cities have a significant influence on construction and transportation—two of the key contributors to global warming emissions. Moreover, because of processes that create climate conflict and climate refugees, city areas are expected to grow during the next several decades, stressing infrastructure and concentrating more impoverished peoples in cities.

High density and urban heat island effect are examples of weather changes that impact cities due to climate change. It also causes exacerbating existing problems such as air pollution, water scarcity, and heat illness in metropolitan areas. Moreover, because most cities have been built on rivers or coastal areas, cities are frequently vulnerable to the subsequent effects of sea level rise, which cause flooding and erosion; these effects are also connected with other urban environmental problems, such as subsidence and aquifer depletion.

Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The modern-day rise in global temperatures is driven by human activities, especially fossil fuel (coal, oil and natural gas) burning since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices release greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, has increased in concentration by about 50% since the pre-industrial era to levels not seen for millions of years.

Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimize future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise.

Climate change vulnerability is a concept that describes how strongly people or ecosystems are likely to be affected by climate change. Its formal definition is the "propensity or predisposition to be adversely affected" by climate change. It can apply to humans and also to natural systems (or ecosystems). Issues around the capacity to cope and adapt are also part of this concept. Vulnerability is a component of climate risk. It differs within communities and also across societies, regions, and countries. It can increase or decrease over time. Vulnerability is generally a bigger problem for people in low-income countries than for those in high-income countries.

Higher levels of vulnerability will be found in densely populated areas, in particular those affected by poverty, poor governance, and/or conflict. Also, some livelihoods are more sensitive to the effects of climate change than others. Smallholder farming, pastoralism, and fishing are livelihoods that may be especially vulnerable. Further drivers for vulnerability are unsustainable land and ocean use, marginalization, and historical and ongoing patterns of inequity and poor governance.

The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of the Danish Realm, which is, by itself, much larger than the combined area of the archipelago), and Iceland (an independent country).

Situated in the northern extremity of North America and covering about 1,424,500 km (550,000 sq mi), this group of 36,563 islands, surrounded by the Arctic Ocean, comprises much of Northern Canada, predominately Nunavut and the Northwest Territories. The archipelago is showing some effects of climate change, with some computer estimates determining that melting there will contribute 3.5 cm (1.4 in) to the rise in sea levels by 2100.

Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. About 31% of Earth's land surface is covered by forests at present. This is one-third less than the forest cover before the expansion of agriculture, with half of that loss occurring in the last century. On average 2,400 trees are cut down each minute. Estimates vary widely as to the extent of deforestation in the tropics. In 2019, nearly a third of the overall tree cover loss, or 3.8 million hectares, occurred within humid tropical primary forests. These are areas of mature rainforest that are especially important for biodiversity and carbon storage.

The direct cause of most deforestation is agriculture by far. More than 80% of deforestation was attributed to agriculture in 2012. Forests are being converted to plantations for coffee, palm oil, rubber and various other popular products. Livestock grazing also drives deforestation. Further drivers are the wood industry (logging), urbanization and mining. The effects of climate change are another cause via the increased risk of wildfires (see deforestation and climate change).

Environmental migrants are people who are forced to leave their home of residency due to sudden or long-term changes to their local or regional environment. These changes compromise their well-being or livelihood, and include increased drought, desertification, sea level rise, and disruption of seasonal weather patterns (such as monsoons). Though there is no uniform, clear-cut definition of environmental migration, the idea is gaining attention as policy-makers and environmental and social scientists attempt to conceptualize the potential social effects of climate change and other environmental degradation. Environmental migration also reflects broader global inequalities, as marginalized and racialized communities often experience the most severe environmental degradation while having the least resources and political power to adapt or relocate. Environmental migrants originate from a variety of different locations, including Small Island Developing States.

"Environmental migrant" and "climate migrant" (or "climate refugee") are used somewhat interchangeably with a range of similar terms, such as ecological refugee, environmental refugee, forced environmental migrant, environmentally motivated migrant, environmentally displaced person (EDP), disaster refugee, environmental displacee, eco-refugee, ecologically displaced person, or environmental-refugee-to-be (ERTB). The distinctions between these terms remain contested.

Climate change adaptation is the process of adjusting to the effects of climate change, both current and anticipated. Adaptation aims to moderate or avoid harm for people, and is usually done alongside climate change mitigation. It also aims to exploit opportunities. Adaptation can involve interventions to help natural systems cope with changes.

Adaptation can help manage impacts and risks to people and nature. The four types of adaptation actions are infrastructural, institutional, behavioural and nature-based options. Some examples are building seawalls or inland flood defenses, providing new insurance schemes, changing crop planting times or varieties, and installing green roofs or green spaces. Adaptation can be reactive (responding to climate impacts as they happen) or proactive (taking steps in anticipation of future climate change).

A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shells or coralline algae. Sediments settle in different densities and structures, depending on the local wave action and weather, creating different textures, colors and gradients or layers of material.

Though some beaches form on inland freshwater locations such as lakes and rivers, most beaches are in coastal areas where wave or current action deposits and reworks sediments. Erosion and changing of beach geologies happens through natural processes, like wave action and extreme weather events. Where wind conditions are correct, beaches can be backed by coastal dunes which offer protection and regeneration for the beach. However, these natural forces have become more extreme due to climate change, permanently altering beaches at very rapid rates. Some estimates describe as much as 50 percent of the earth's sandy beaches disappearing by 2100 due to climate-change driven sea level rise.