365 Days of Climate Awareness 333 – AR6 Vol. 2, Chap. 6: Cities, Settlements and Infrastructure

The growth of cities in both area and population density has increased climate threats to them, particularly since the most rapid urban growth in the last two decades has happened in still-developing countries where other climate impacts are being felt. In most cases compound or cascading problems threaten the livelihood of people or the entire existence of the city. Further, generally due to geographic constraints, such as poor neighborhoods being shunted to lower-lying areas, climate threats in cities tend to be concentrated on lower-income areas. These trends are expected to worsen, as it is expected that 2.5 billion people will move closer to the coast around the world by 2050.

From IPCC AR6, Vol. 2, Chap. 6. Definitions of settlement types. 

From IPCC AR6, Vol. 2, Chap. 6. Anticipated spread in flood zones through 2100.

Responses at the national and citywide level have varied tremendously around the globe, for a number of reasons. First among them is money, available capital for mitigation projects such as seawalls and aqueducts (where groundwater withdrawal is causing widespread subsidence, as in Jakarta). Second is awareness and political will. In many developing countries, the governments lack resources or are corrupt or unstable enough, with severely divided populaces, such as in Nigeria, to effectively address climate change problems (such as flooding in Lagos). In many respects climate change has remained a developed-world problem, both in its causes and mitigation methods, even though developing nations, generally in more environmentally vulnerable locations, are disproportionately feeling the effects.

Increased risk to flooding: anticipated affected population through 2100, at +4°C/7.2°F

Increased risk to flooding: anticipated damage through 2100, at +4°C/7.2°F

In the developing world, urban expansion has been at the center of national development strategies. As these countries around the world have looked to emulate the economies of OECD (Organisation for EconomicCo-operation and Development) nations, they have aggressively sought to expand coastal cities especially. Meanwhile urban planning has not often included the most recent, and decidedly more expensive, innovations in water and energy use. This has led to the growth of huge coastal cities around the world with even larger environmental impacts, through groundwater uptake and greenhouse gas emissions, than would have happened with more environmentally conscious planning.

From IPCC AR6, Vol. 2, Chap. 6. Global risk of hyperthermia (including heat sickness, heat stroke and death): (top) present; (middle) 2050; (bottom) 2100.

From IPCC AR6, Vol. 2, Chap. 6. Adaptation gaps by economic stratum (higher vs. lower). Blue: historical. Orange: planned through 2100. Columns: specific type of adaptation planning. Rows: geographical region.

Tomorrow: Health and well-being.

Be brave, be steadfast, and be well.

IPCC 6th Assessment Report, Vol. 2, Chap. 6