Demographic Change & Climate Change Flashcards
Differentiation
1) Weather vs climate
‘Weather’ refers to the temperature and precipitation at a specific time and place, whereas ‘climate’ refers to the weather in a location averaged over long periods of time
Differentiation
2) Climate vs environmental change
‘Climate change’
- refers to a sustained change in the average long-term levels of temperature and precipitation, whereas ‘climate variability’ refers to a sustained change in the longterm variance around these average levels
- expected to be paralleled by increases in extreme weather events (e.g. heat waves), rising sea levels, more (intense) floods & droughts, resulting in degradation of land & fresh water resources, lower food security, etc. …
‘Environmental change’ is a broader concept: It can result from oil spills, land degradation, deforestation, etc.
Are demographers concerned about climate change?
- Very to Extremely worried
- Hardly any challenges in the twenty-first century are greater than those arising from the interaction of demographic change and climate change
- We know with near certainty that future global climatic conditions and the size and structure of global populations will be different from those observed today (i.e. Eastern Africa will be larger, older, and probably better educated)
in need of models with predictive power on both sides BUT big asymmetry: highly sophisticated models from natural sciences but nothing comparable in social sciences, very few models that can provide alternative future scenarios of population and human development
Interaction of climate change & population dynamics (model)
- Solutions to mitigation (reductions in emissions) depend on technological advance and consumption - behavioural changes
- Capacity to do so will again depend on the demographic composition of the population and in particular on its level of education.
- However, the ability to cope with the consequences of climate change also varies greatly at the level of the individual, the household, and the community.
- Differential vulnerability according to demographic characteristics such as age, sex, place of residence, or level of education has to be taken into account when assessing the likely impacts of changing climate conditions on mortality, health, livelihood, or migration.
How will changes in population composition effect climate change?
1) Aging & Urbanization
1) Aging Population
- should generally drive carbon emissions down (due to changes in consumption patterns - transportation - and reduced labor productivity)
- but may also increase energy use for heating and cooling of floor space (O’Neill and Chen 2002)
2) Urbanization is associated with …
- technical innovation, access to information, efficient land and energy use, as well as lower fertility (=> reduction in carbon emissions)
- rising labor productivity and incomes, ‘urbanized’ life styles and consumption patterns (=> increase in carbon emissions)
-> Evidence/projections thus provide mixed results (depending on period/region, short-/long-term perspectives)
Under the integrated assessment framework, an analysis using the PET model had been conducted to explore the combined effects of changes in household age structure and urban–rural residence in China –> estimate of carbon emissions is 45% higher in 2100 than projections that do not incorporate aging and urbanization
How will changes in population composition effect climate change?
2) Education & fertility
3) Education (Lutz & Striessnigg 2015)
- is positively associated with more ‘eco-friendly’ consumer choices at any given level of income
- has been shown to reduce people’s vulnerability and to strengthen their adaptive capacity (!)
- fosters economic growth (innovations) and – importantly – reduces fertility
4) Fertility
- decline slows population growth, reduces the pressure on livelihoods, and frees resources that can be used to cope with climate change.
- “While the rest of the world wrestles with the complexities of reducing emissions, the poorest countries will benefit from simple programs to lower fertility.” (Das Gupta 2014)
Population policies:
a suitable response to climate change?
- Embedded in a broader set of development policies, population policies and programs promoting education as well as universal access to voluntary contraception and addressing demographic factors such as urbanization and aging will contribute to a more sustainable demographic future that plays a crucial role in climate change mitigation and adaptation
- BUT population policies are highly controversial & European demographers are therefore highly divided on the questions:
(a) whether the global population size should be reduced to lower CO2 emissions
- ideological problem: LDCs are not main contributors
- who & what decides when growth is too low/high?
- population decline is a mixed blessing: it perhaps alleviates the concerns of overpopulation, but it may also hamper economic growth
(b) whether family planning is an effective policy instrument at all
Role of climate change in fertility outcomes
barely any empirical research yet, but several plausible pathways linking climate change and fertility
- potential mechanism include: sectoral reallocation (agriculture), (child) mortality, migration, armed conflicts
- example: the differential effect of climate change on relative sectoral productivity will affect parental decisions about fertility levels and education for children. In high latitude countries, which tend to be richer, climate change may lead to lower fertility and higher skill accumulation, the reverse of what we find for low latitude countries. These forces may increase the income gap between the richer high-latitude countries and poorer equatorial countries.
Heat-related mortality?
- Between 1991-2018, 37% of all warm-season heat-related deaths in 43 countries could be attributed to anthropogenic climate change
- By the end of this century, climate change (reflected in ‘very hot’ days) is projected to increase age-adjusted US mortality rates by 3% BUT between 1900-2004, the mortality impact of days with a mean temperature >27°C declined by 75%
- ->This decline in the US almost entirely results from the diffusionof residential air conditioning –> residential energy consumption is estimated to increase by 11% over the course of this century!
Excursus: Demographic amplification of climate change - US during 20th century
Americans moved to warmer, drier regions throughout 20th century
Consequences:
- Population redistribution to warmer, drier regions will exacerbate recent and precicted increases in water stress and electrical demands for thermal comfort through air conditioning
- Given that the change in climate exposure observed in this study is in the same direction as the anticipated climate change caused by greenhouse gas emissions, it is likely that the economic burden of climate change during this century will be much greater and regionally disparate than predicted because of demographic amplification of climate change.
Cold-related mortality
1) direct: freezing to death
2) indirect: catching a cold
UK study:
- Reductions in cold-related mortality may (initially) outweigh increases in heat-related mortality:
the 2050s, heat-related deaths would rise by around 257% (in the absence of adaptation); cold-related mortality would decline by 2%. - BUT cold burden remains higher than the heat burden in all periods!
- Population aging as an amplifier: oldest-old population at highest risk! –> BOTH cold & warm-related deaths!
Climate change: air pollution & mortality
Climatic influences on infectious diseases
➢ If global warming amplifies “El Niño” type phenomena, regions surrounding the Pacific and Indian oceans are expected to be the most vulnerable ones with higher incidences of …
- malaria in South America
- rift valley fever in East Africa,
- dengue fever in Thailand,
- hantavirus pulmonary syndrome in the southwestern USA,
- childhood diarrhoeal disease in Peru,
- cholera in Bangladesh.
➢ Adaptation: Early warning systems for heatwaves (can go to supermarket with ACs..) and for expected outbreaks of infectious diseases …
“Environmental migrants”
1) Definition
People forced to leave their traditional habitat, temporarily or permanently, because of a marked environmental disruption (natural and/or triggered by people) jeopardizing their existence and/or seriously affecting their quality of their life
3 types of “Environmental migrants”
- temporarily displaced because of environmental stress (usually a natural disaster)
- permanently displaced and resettled in a new area
- internal migrants due to deterioration of the resource base in their original habitat
“Environmental migrants” - Numbers
- increasing from ~25 million at the turn
of 2000 to ~200 million in 2050 - BUT evidence base is “varied and patchy”, ranging from “substantial” to “minor” impact of climate change on human migration.
Direct vs indirect effect of climate change on migration
- Environmental change has the potential to affect directly the hazardousness of place, but – more importantly – it also affects migration indirectly through i.e. economic (income, job opportunities) and political (conflicts) drivers –> The effect of the environment is highly dependent on the economic, political, social and demographic context.
- Future environmental change will only have an incremental direct impact on (international) migration flows. It will rather amplify (or alter) existing demographic trends of migration.
- In less developed countries adverse weather/climate conditions are more likely to stimulate internal and shorter-distance moves or even to “trap” populations in place (costs of migration) –> Sub-saharan Africa
