Patterns in environmental quality and sustainability Flashcards
definition of global warming and climate change
the observed century-scale rise in the average temperature of the Earth’s climate system and its related effects, which has been noticed since the 1980s
(rainfall, temperature, sea level, habitats, drought, floods and storms)
WHILE IT IS IMPORTANT TO NOTE THE GENERAL RISE OF TEMPERATURE, IT IS EVEN MORE IMPORTANT TO BE CONGNISANT OF THE EXTREMES!!
definition of the greenhouse effect
The process by which certain gases (water vapour, carbon dioxide, methane and chlorofluorocarbons) allow short-wave radiation from the sun to pass through the atmosphere and heat up the earth, but trap an increasing proportion of long-wave radiation from the earth. This radiation leads to a warming of the atmosphere.
the enhanced greenhouse effect
the increasing amount of greenhouse gases in the atmosphere as a result of human activities, and their impact on atmospheric systems, including global warming
insolation and its effects on weather systems (+ redistribution of energy)
incoming solar radiation
Solar energy drives all weather systems and climates (wind energy is second order solar energy). The earth absorbs most of this energy in tropical areas, whereas there is a loss of engird from more polar areas. To compensate for this there is a redistribution of energy to higher latitudes from lower latitudes, caused by wind- and ocean circulation.
radiation
convection
conduction
radiation — the emission of electromagnetic waves such as X-ray, short wave and long wave; as the sun is a very hot body, radiating at a temperature of about 5,700°C, most of its radiation is in the form of very short wavelengths such as ultraviolet and visible light
convection — the transfer of heat by the movement of a gas or liquid
conduction — the transfer of heat by contact
insolation and the atmosphere
Only 50% of the insolation at the top of the atmosphere actually gets through the earth’s surface. 30% is reflected, 20% absorbed by atmospheric gases (especially oxygen and ozone at high altitudes, and CO2 and water vapour are low altitudes), scattering accounts for 6% lost insolation, (cumulus/thick) clouds reflect 23%, earth reflects 7% of insolation (planetary albedo).
long-term and short-term variations of climate change
In long timescales, the earth’s temperature changes whenever the input of solar energy changes:
- earth’s orbit changes slightly, creating ice ages and seasons
- sunspots and solar eclipses also reduce solar energy temporarily and alter wind patterns.
On a shorter timescale, changes in the atmospheric composition can change global temperature dramatically.
factors that effect earth’s albedo
melting ice sheets (positive feedback)
hence, indirectly greenhouse gases
irrigation (darker soil in deserts)
overexploation of lakes and rivers; decreasing water surface
factors effecting climate change
- As ice melts, albedo/reflectivity reduces and insolation absorbed increases and temp. rises.
- Increased burning of fossil fuels (coal, natural gas, oil) makes the atmosphere absorb and reradiate more heat, increasing global temperature.
- Burning of rainforest releases CO2 — leaves fewer trees to absorb CO2. The atmospheric concentration, ppm, increases exponentially (double whammer).
- Methane produced by domestic animals and landfills: cattle convert up to 10% of their food into methane. As global warming increases, bogs (marsh) trapped in permafrost will melt and release vast quantities of methane. Methane increases at a rate of 1% per annum.
- Chlorofluorocarbons (CFCs; aerosols) are synthetic chemicals that destroy ozone, as well as absorbing long-wave radiation. CFCs increase at a rate of 1% per annum and are up to 100 000 times more efficient at trapping heat than CO2. They also create holes in the ozone layer.
- Transport pollution contribute to greenhouse gases
all disturbed the natural balance:
CO2 from humans, animals = CO2 taken by trees
O2 given out by trees = O2 used by humans and animals
implications of climate change
- Sea levels will rise (thermal expansion & ice melt), causing flooding, displacing hundreds of millions of people.
- Storm severity and frequency will increase (owing to more atmospheric energy)
- Agricultural patterns will change (leaving less time for farmers to grow)
- Droughts, fire, erosion, landslides, sedimentation, avalanches, pests and diseases intensity and frequency increases
- Up to 40% of species of wildlife will become extinct
However, this is just a fragment of what will expect us, and with a big uncertainty no knows exactly what will await us, except that everything will become more extreme. For instance, some suggest that certain areas might get colder, such as northwest Europe if the Gulf stream shuts down.
soil degradation
the decline in quantity and quality of soil. It includes:
- erosion by wind (28%) and water (56%)
- biological degradation (the loss of humans and plant/animals life)
- physical degradation (loss of structure, changes in permeability) (4%)
- chemical degradation (acidification, declining fertility, changes in pH, salinisation, chemical toxicity) (12%)
All this will increase with climate change.
predicting soil erosions
calculated by the universal soil loss equation A = RKLSCP, with factors that increase susceptibility to erosion
Ecological Conditions:
- Erosivity of soil R
- Erodibility K
- Length-slope factor LS
- Land-use type
- Crop management C
- Soil conservation P
Causes of soil and land degradation include:
- the reduction of the natural vegetive cover which renders the topsoil more susceptible to erosion, as when huge areas of forest are cleared for logging, fuelwood, farming or other human uses (although some areas are becoming greener, such as Europe’s forest cover)
- unsustainable land-use practices such as excessive irrigation, inappropriate use of fertilisers and pesticides, and overgrazing by livestock
- groundwater over-abstraction, leading to dry soils, leading to physical degradation
- atmospheric deposition of heavy metals and persistent organic pollutants, making soils less able to sustain the original land cover and land use
Again climate change will intensify this problem. // Nature takes 500 years to replace 25mm of topsoil lost to erosion.
Removal of vegetation and topsoil frequently results in
- increased surface runoff and stream discharge
- reduction of water infiltration (chemical contamination) and groundwater recharge (falling levels)
- development of erosional gullies and sand dunes
- change in the surface microclimate that enhances aridity
- drying up of wells and springs
- reduction of seed germination of native plants (invasion of alien plants)
Socio-economic impacts include a lack of farm productivity, rural unemployment, migration, silting of dams and reservoirs, hunger and malnutrition. This is no a poor-nations-problem.
the current state of soil degradation
In 1990, over 30% of soils were considerable to moderately or severely damaged. The main points:
- Soil is one of the world’s most important resource
- Soil is a non-renewable resource that is easily destroyed
- Farms must use methods to preserve soil quality (protection against erosion and pollution - organic farming, afforestation, pasture extension, benign crop production)
- Urban development causes great damage to soil
- Soil must be managed in a sustainable way
Tackling soil degradation and contaminated soil
Tackling soil degradation:
- physical barriers: embankments and windbreaks, vegetation cover and soil husbandry
- mechanical: bunding, terracing (which additionally also increases cultivated area), contour ploughing, shelter belts such as tress or hedges (to key is to prevent or slow the movement of rainwater downslope and wind).
- the crop should be in the soil for as long as possible due to the strengthening roots, which is the reason why farms often leave the root structures in the field. Also, increased organic material allows the soil to hold more water, thus preventing aerial erosion and stabilising the soil structure.
Tackling contaminated soils:
- flossing the soil and leaching the soil away
- applying chemicals such as gypsum to replace sodium ions on the clay and colloids with calcium
- reducing evaporation losses to lessen the upward movement of water in the soil
more causes (socio-economic) of soil degradation
Natural disaster
Degradation due to biogeographical causes
Population change
Degradation occurs when population growth exceeds environmental thresholds (neo-Malthusian), or when decline causes collapse of adequate management
Underdevelopment
Resources exploited to benefit world economy or developed countries, leaving little profit to manage or restore degraded environments
Internationalism
Taxation and other forces interferer with the market, triggering overexploitation, commercialisation
Colonial legacies
Trade links, communications, rural-urban linkages, cash crops and other “hangovers” from the past promote poor management of resources exploitation.
Inappropriate technology and advice
Promotion of wrong strategies and techniques that result in land degradation
Ignorance & Attitude
Linked to inappropriate technology & advice: a lack of knowledge of what leads to degradation, plus blaming attitudes of institutions and people, lack of awareness
War and civil unrest
Overuse of resources in national emergencies and concentrations of refugees, leading to high population pressures in safe locations.
Water usage increases with population growth, resulting in:
- overexploitation of rivers
- half of the wetlands disappeared
- 20% of freshwater species are endangered or extinct
- many important aquifers are being depleted
- water tables are dropping alarmingly
water stress
when per capita water supply is less than 1,700 cubic metres per year
This will be a severe problem in many regions like Africa, Middle East and south Asia, which may lead to conflicts. Currently, 2.3 billion live under water stress, 3.5 billion (48% of the world projected population) in 2025.
water scarcity
depends on precipitation and water availability, population growth, demand for water, affordability of supplies and infrastructure.
- physical water scarcity: water consumption exceeds 60% (unsustainable) of the useable supply. Then countries depend on imports and desalination plants (e.g. Saudi Arabia and Kuwait).
- economic water scarcity: physically sufficient water but additional storage and transport facilities are needed, required expensive water-development projects (e.g sub-saharan). Due to inefficient technology in LEDCs farmers use twice as much water as in MEDCs yet yields are three times lower.
how many people die from poor water quality
how many lack access to safe water, adequate sanitation, and wastewater treatment
because of overpopulation in urban areas, ineffecient aid flows (curruption) and numerous other factors:
Inadequate water quality causes 4 million deaths annually from water-related diseases, particularly cholera, hepatitis and malaria (parasitic diseases). Water quality is affected by sewage, fertilisers, pesticides, heavy metals and acids from industry and transport.
1.1 billion lack access to safe water, 2.6 billion are without adequate sanitation, 4 billion do not have their wastewater treated to any degree.
climate change and the hydrogical cycle
While the world as a whole will get wetter as warming speeds up the hydrological cycle, increased evaporation will make drought conditions more prevalent. Most places will experience more unpredictable, intense and variable precipitation, with longer dry periods between them, so that traditional agricultural and water management practices are no longer useful.
- To manage water well, it is crucial to know how much water is available in any basin and what it is used for.
policies tackling climate change
carbon dioxide tax
water policies to allocate water efficiently and limit consumption to safe levels. Tradable water rights could improve water management in the long term but are not realistic short-term options in most developing countries.
Climate change will require investing in new technologies and improving the application of existing technologies. Water supplies can be enhanced by desalinating seawater or brackish water and reusing treated wastewater - RECYCLING.
agriculture and climate change
Climate change will depress agricultural yields, and so we will need to increase productivity while protecting the environment. Efforts to mitigate climate change will put more pressure on land, and with growing populations, more carnivores tastes and increased demand for dairy products, the world will require highly productive and diverse agricultural landscapes.
example of managing waters: Tunisia (good) and China (bad)
Tunisia built dams with conduits to connect them and to transfer water between different areas. Stored water can be pumped across the mountain range to river basin. New water both increases supply and dilutes the salinity in the area where demand is highest. A thirds of urban wastewater is treated and reused for agriculture and wetlands, recharging aquifers artificially.
In China, underground water table is falling by a meter a year, due water hungry industries such as rice and megacities like Beijing. Water tariffs aimed to reduce water usage. Industries recycle 15% of their waste water, compared to 85% in developed countries.
importance of tropics (detrimentality of rainforest destruction)
Tropics (rainforest) are the richest area for biodiversity, containing over 50% of the world’s species in just 7% of the world’s land. They account for 80% of world’s insects and 90% of primates.
They not only have impacts on biodiversity, climate buffering, rainfall generation and soil stabilisation, but also health impacts, as well as industrial and recreational benefits.
Rainforests contain a vast store of water, and cool earth by realising water in the atmosphere. In Brazil alone, the Amazone releases about 20 billion tonnes each day.
Why is the destruction of the rainforest so detrimental?
A releases 8-10 times more moisture into the atmosphere than a square metre of ocean water. Remove a tree and the water store disappears. Then, less water re-evaporates from the vegetation, and so the recycling of water diminishes. Thus mean annual rainfall is reduced, and the seasonality of rainfall increases. Furthermore, deforestation disrupts the closed system of nutrient cycling within tropical rainforests. In-organic elements are realised through burning and are quickly flushed out of the system by the high-intensity rains. CO2 is released by burning and leaving less trees to absorb it. Soil erosion increases. As a result of soil compaction, infiltration decreases, and overland runoff and surface erosion increases. Desertification occurs as everything but heavier sand is washed away by rain. As a result of the intense surface runoff and soil erosion, rivers have a higher flood peak and a shorter time lag. Warmer climate creates lower river levels, creating greater turbidity (murkiness).
Case study: Deforestation of tropical rainforest in southeast Asia
Forests in southeast Asia cover some 136 million hectares. It is predicted that by 2050 this natural forest will have been converted into agricultural land, forest plantation and other non-forested uses. Rates of annual forest loss in southeast Asia from 2000-2005 range from 0.5% for Papua New Guinea to 2% for Indonesia. In 2007, Indonesia was reclassified as the third largest contributor to global greenhouse gas emissions after the US and China.
Major threats to southeast Asian forests
Rapid population and economic growth is driving the degradation of these forests:
- industrial logging concessions, worth about US $10.4 billion per annum
- illegal logging, especially in Indonesia, leading to an estimated US $4 billion in lost government revenues per annum
- agriculture, predominantly palm oil and rubber, worth about US $17.8 billion per annum and using some 7.6 million hectares of land
- burning and drainage of carbon-rich forested peatlands, particularly in Malaysia and Indonesia
- mining and petroleum, particularly in Papua New Guinea where it contributes 25% of GDP annually.
The effect of deforestation in southeast Asia is likely to have a major impact on rainfall generation. In addition to the carbon stored in its forests, at least 42 billion tonnes of soil carbon are stored in the forested tropical peatlands of southeast Asia. The region is also home to four of the world’s 25 biodiversity hotspots. On account of the region’s unique geological history, Indonesia and parts of Malaysia reach 60% endemism for plants and reptiles and 80% for amphibians; Papua New Guinea tops 80% endemism for mammals, reptiles and amphibians.
“social” foresty (lies of TNCs) - illegality
In Congo, one of many examples, representatives of major timber firms (e.g. Danzer, Trans-M, TB, NST, Olan, Sicobois) arrive in the towns to negotiate with the traditional landowners. The companies promise to build schools and pharmacies. These “social responsibility” agreements are encouraged by the World Bank, but these are just meaningless words and make the owners sell their forest cheaply. The companies creates road networks deep into the forest and begin exporting the wood all over the world, without the villages ever seeing any schools or pharmacies. They exploit the situation of those people who were just recently plagued by civil wars and dictatorships. The effects of logging (in Congo), are dramatic, as 20 million hectors have been given over to logging firms. 80% of logging is illegal. If forest felled, up to 34 billion tonnes of carbon could be released, 8% of the earth’s carbon. The World Bank access that logging could destroy the forest in a short time, leading to immense social problems. These forests depend on donors like these, but they choose to leave the situation lawless.
use of the environmental sustainability index (ESI) and the results and patterns of the ranking
gives clear environmental objectives:
- reducing environmental stresses to human health
- promoting ecosystem vitality and sound natural resource management
The most sustainable countries, as ranked by the ESI are wealthy, sparsely populated nations with an abundance of natural resources (e.g. Switzerland, Sweden).
The only developing countries in the top 10 are Costa Rica and Columbia, both of which have relatively low population densities and an abundance of natural resources. Conversely, the only density population countries that have received above average ratings are Japan, Germany, the Netherlands and Italy, some of the richest countries on the list.
Effects of climate change on sustainability
Poor people need environmental sustainability because they are highly dependent on the environment and its resources (fresh water, crops, fish, etc.), which provide roughly two-thirds at household income for the rural poor.
The effects of climate change include increased rainfall variability (meaning more droughts and increased flooding), reduced food security, spread of disease, increased risk of accidents and damage to infrastructure. The poor are most vulnerable to these changes and have limited capability to respond to them.
facts and figures about climate change
Overfishing has led to the collapse of many fisheries. A quarter of global marine fish stocks are currently overexploited or significantly depleted.
About 60% of the ecosystem services resources evaluated by the UN’s Millennium Ecosystem Assessment are being degraded or used unsustainable.
Between 10% and 30% of mammal, bird, and amphibian species face extinction.
Global timber production has increased by 60% in the past four decades. This means that roughly 40% of forest area has been lost and deforestation continues at a rate of 13 million hectares per annum.
unequal power to change
Those who are affect the most have the least political influence (the poor) and those who are most influential in policy development have little understanding of the costs and benefits associated with environmental policy. Economic growth and the environment are often still viewed as competing objectives, even though investing in environmental management can be cost-effective, and contributes to improved livelihoods.
Suvivor bias - those who are wealthy think nothing is bad.
the true cost of environmental inaction
A recent World Bank study provides stark assessment of the risks and enormous costs if no remedial action is taken. For example, the annual losses to Nigeria of not acting on its growing environmental problems are estimated to be more than US$ 5,000 million annually.
