Land Use and Urbanization Dynamics

With all these issues in mind, from climate change to climate adaptation to adaptive capacity, there are several ways to refine these concepts for application. One

phenomenon in particular has not been well addressed in discussions of measuring adaptive capacity, and that is urbanization. This section hopes to draw connections between urbanization, land use and land cover (LULC) change, climate and adaptive

capacity, as “accelerated urbanization is an important trend in human settlement, which has implications for the consideration of exposure and vulnerability to extreme events”

(IPCC 2012).

In 2014, 54% of the world’s population lived in urban areas, and that figure has

surely risen since. Urbanization is expected to continue well into the future all over the world. By 2050, the global urban population is predicted to be two thirds of the global

population, with most of the change concentrated in Africa and Asia. Asia, in particular, will continue to hold about half of the world’s urban population. Driven by a number

of social and economic transformations, urbanization catalyzes a number of its own changes, affecting the state of poverty, of land use and land cover, and more. This has, and will continue to have, a great effect on demographic and environmental developments. (UN WUP 2014)

World urbanization has a profound impact on the extent and spatial character of urban land cover and land use. With geographic movement of demography comes geographic change of resources, capital, and demand, all of which have corresponding physical manifestations. With more people living and working in cities, metropolises

expand and agricultural and natural vegetated land cover is developed, increasing the concentration and total area urban land. Natural land cover, due to its physical and chemical properties, has cooling and water retention functions, as well as important for soil and ecological health. Transition to urban land cover can lead to the heat island effect and pollution problems. Thus when urbanization causes a decrease in natural land surface it affects carbon, energy, and water budgets, and a number of other biophysical mechanisms with far reaching consequences (Dale 1997, Pyke and Andelman 2007, Pielke et al 2011).

Land use and land cover (LULC) and urbanization are also both major drivers

and results of global climate change (Dale 1997, Kalnay and Cai 2003, van der Werf

and Peterson 2009). LULC have complex interactions with atmospheric conditions, which contributes to climate change while simultaneously compounding or mitigating climate impacts at a range of scales (Dale 1997, Pyke and Andelman 2007, Lee 2009, Pielke et al 2011). Most notably, deforestation can add significantly to carbon dioxide levels by releasing carbon from vegetation, and removal of wetlands can have similar effects. Conversely, climate impacts can also spur urbanization or reallocation of agriculture land or pasture land (Lee 2009). Pyke and Andelman (2007) state that “the impact of global climate change is mediated at regional and local scales by biophysical processes associated with LULC.” LULC and climate change are intimately linked;

both climate mitigation and adaptation are influenced by, and in turn influence back, LULC and urbanization.

These have impacts on both socioeconomic and biophysical systems. More specifically, LULC affect soil moisture, length of growing season, diurnal temperature range, temperature extremes, suspended dust volumes, rainfall patterns, albedo, and storm frequency, which all influence agricultural production and thus food security.

Urban land increases heat at lower levels of the atmosphere and can change peak heat times and elevate minimum temperatures, affecting thermal comfort and health. The increase in impervious surfaces and decrease in forest coverage that comes with urbanization tend to have negative effects on ecological functions, such as loss of soil fertility or decline in species diversity. Thus, from both historical data and modeling results, it has been shown that climate is intertwined closely with changes in LULC.

As mentioned before, changes in land use have clear, observable effects on greenhouse gas emissions and vice versa (Liao et al 2013, Jones et al 2013). But it would be remiss not to realize that climate adaptation is also mediated by LULC. Many determinants of adaptive capacity are affected by levels of urbanization as LULC have effects on both social and ecological systems. Socioeconomic determinants, like access to resources or income level, are highly related to urbanization. The rural-urban disparity is key in considering factors that influence adaptive capacity. Many economic

resources are concentrated in urban areas, as they are linked to international markets and finance. Also, urban areas tend to be well serviced by infrastructure from roads to electricity, compared to rural areas that may not have as easy access to things like running water or cellular service. But cities are complex places, and have both positive and negative impacts on adaptive capacity. Cities may be associated with more resources, but they also bring many consequences like increased inequality or weaker social ties that provide support in times of stress. Biophysical factors are also often dependent on land cover, as previously mentioned; for example, flooding impacts are exacerbated by loss of coastal wetlands and wetlands have historically been filled in for the sake of agriculture or other kinds of development. Forest cover has also been shown to have cooling effects, or other positive impacts on soil retention or precipitation patterns.

Studies have shown clear links between LULC and climate change and the feedback between them, but a literature gap remains in drawing connections between LULC change and measuring adaptive capacity, although SREX addressed urbanization specifically as a potential driver of vulnerability. This study aims to use the existing literature to create a new measure in which to connect the effects of urbanization on the ability of communities like Tamsui and West Palm Beach to adapt to oncoming climate change.