climate change

Global Temperature Distribution

Temperatures generally influenced by latitude - higher latitudes lower temperatures and vice versa Exceptions in Himalayas and Andes where the main influence on temperature is altitude - mountainous areas. Exceptions also in largest continental masses in North America, Asia and Antarctica - lower temperatures due to Continental effect.

5 Factors affecting local temperature Latitude

\ Lower Temperatures at higher Latitudes:At higher latitudes, or temperate or polar regions, the sun's rays strike the surface at a larger angle. This causes the sun's rays to be spread over a larger area, and are therefore less concentrated, resulting in lower temperatures.

The sun’s rays also pass a longer distance through the atmosphere above temperate/polar regions. This results in more heat energy lost through reflection, absorption and scattering by dust particles and water vapour in the atmosphere → lower temperatures. Higher Temperatures at lower Latitudes: Due to the earth's curvature, the sun's rays strikes regions near the equator and between the tropics perpendicularly. This means the sun's rays fall on a smaller surface area at equatorial regions, and are more concentrated. Also, due to the curvature of the earth's surface and the atmosphere around the earth, the sun's rays pass a shorter distance through the atmosphere above the equator. These 2 conditions result in higher temperatures.

Both the distance traveled through the atmosphere and the concentration of sun's rays cause this relationship: Temperatures are inversely proportional to latitude. Altitude

The Normal Lapse Rate: For every 1000m rise in altitude in the Troposphere, there is a 6℃ decrease in temperature. 2 reasons for this: Air is thinner in the upper troposphere, which means there are less air particles that trap and re-reflect heat. (Gravity pulls air particles towards lower altitudes) Most of the heat we feel this close at the lower troposphere is due to terrestrial radiation. Re-radiated heat from the earth. The further we go up in the troposphere, the further we are from terrestrial radiation. Albedo

Albedo is measured on a scale of 0-1 or as a %. 0 means that the surface of a material absorbs all of the sunlight that hits it. 1 means that a material reflects all of the light energy that hits it. Lighter coloured materials such as snow and grass have significantly higher albedo. In developed areas with lots of buildings and people, the effect of albedo can contribute to a phenomenon known as an urban heat island. When cities replace natural land cover with dense concentration of buildings, pavements, etc, these surfaces absorb and retain more heat. The region will have a higher average temperature compared to rural areas. Distance from the sea

Coastal areas experience milder seasons due to the Maritime Effect. The presence of large bodies of water at coastal areas have an insulating effect. During Summer, coastal waters take a long time to heat up. Air above the seas/oceans exchange with air above coastal land, cooling the land, causing lower temperatures during summer. During winter, coastal waters take a longer time to lose heat, and its retained warmth exchanges with the colder air above coastal land, causing higher temperatures during winter. Hence, coastal areas have a smaller annual temperature range through the seasons. Maritime & Continental Effect Coastal areas tend to have milder, less wide ranging temperatures through the seasons of a year. Inland areas tend to have hotter summers and colder winters.

Inland areas experience more severe seasons due to the Continental Effect: During Summer, Inland areas have no large enough body of water, and will continue to heat up, and become very warm. In Winter, Inland areas will lose heat indefinitely until the season changes, resulting in very low temperatures during Winter. Cloud Cover

Causes of Climate Change

The Earth Energy Budget & Global Warming In spite of the enormous transfers of energy into and from the Earth, the Earth maintains a relatively constant temperature. There is little net gain or loss: Earth emits via atmospheric and terrestrial radiation to space about the same amount of energy as it receives. The role that the atmosphere plays is crucial in understanding climate change: A great amount of heat, or infrared radiation that is experienced within the troposphere is due to how the atmosphere traps terrestrial radiation.

The Enhanced Greenhouse Effect Anthropological or human activities since the industrial revolution have seen increased amounts of greenhouse gases in the atmosphere. Carbon Dioxide and Methane are the most common anthropogenic gases, and also trace amounts of Nitrous Oxides. These gases absorb and re-emit terrestrial radiation, and do so in any direction. As a result, an increasingly larger proportion of terrestrial radiation no longer escapes into space, but is trapped within the troposphere.

WA 2 Starts here! Anthropogenic Causes of Climate Change

\ POSITIVE FEEDBACK LOOPS causing greater global warming Feedback loops: Increased temperatures on the Earth have consequences that may result in conditions that either make temperatures higher or lower. Anthropogenic causes of climate change are usually POSITIVE feedback loops - their consequences cause even greater temperature increases. Melting Ice Caps The increased greenhouse gas emissions by man has caused melting of ice caps and glaciers both in the North and South Poles. The melting ice turns in "sick" ice - pools of black water between still solid ice. These black pools have low albedo and further absorbs heat. On a larger scale, "sick" ice accelerates the melting process, and the Arctic has lost up to 90% of its ice during the Summer extremes. DeforestationThe clearance of forests, especially through burning, has multiple direct impacts on greenhouse gas emissions. Forests, and the soil that forests are on, are a huge carbon sinks, at about 2000 Gigatonnes. Removal of forests usually means the loss of soil and results in a large amount of carbon finding its way into the atmosphere as a greenhouse gas. This is further compounded by the fact that forests are the main way in which carbon is fixed to become oxygen. Loss of forests usually also means less evapotranspiration in the area, and less clouds and rainfall. This can cause previously forested areas to become desert-like, through a process called desertification. This land becomes non-arable, and unable to grow any vegetation - which in turn causes greater global warming. The main area of forests being depleted right now is the Amazon Rainforest which has already lost 60% of its biomass. Peatland & Swamps Areas with peat are wetlands such as swamps, bogs and marshes. Decomposition in these areas releases methane, but vegetation makes up with carbon fixation. But traditionally swamps are ALWAYS cleared by man - and this releases the methane and carbon dioxide. The loop occurs when rising temperatures also affects uncleared or protected swamps. Rising temperatures make Methane more volatile - and escapes the swamp regardless of vegetation.

Negative Feedback Loop: Increased ocean temperatures have led increased evaporation rates and increased cloud formation. Low lying clouds are thick and dense and have high albedo and can possibly reduce incoming solar radiation. However clouds can also trap heat within the lower atmosphere, increasing local temperature. Generally, clouds that form at lower levels in the troposphere cause a negative feedback loop due to their thickness, and have a net cooling effect despite trapping some terrestrial radiation. While clouds at higher levels are too thin and allow all solar radiation through, and have a net warming effect.

Natural Causes of Climate Change

Ice Core data reveal that climate change has occurred on the earth for as long as 800,000 years. The earth seems to fluctuate between Ice Ages and Interglacial periods, with temperatures peaking every 100,000 years or so. This is evidence that climate change does occur naturally, and without any kind of human input. However, recent CO2 concentration levels seem to be unprecedented - reaching 380 parts per million, while the Ice Core records only up to 300ppm. This seems to indicate anthropogenic activities can push CO2 levels unnaturally high, and hence global warming.

Milankovitch Cycle - Eccentricity Today a difference of only about 3 percent occurs between aphelion (farthest point) and perihelion (closest point). We are supposedly at a phase with minimal eccentricity. This 3 percent difference in distance means that Earth experiences a 6 percent increase in received solar energy in January than in July. When the Earth's orbit is most elliptical (elongated) the amount of solar energy received at the perihelion would be in the range of 20 to 30 percent more. These continually altering amounts of received solar energy around the globe most certainly result in prominent changes in the Earth's climate. Current inferences made about greater eccentricity: Greater amounts of time spent further from the sun (at the aphelion) will mean deeper winters and greater chance for stabilization of glaciers and ice sheets. This has a positive feedback loop towards GLOBAL COOLING (or dimming), since the lowered temperatures cause the glaciers and ice sheets to stabilize which cause increase albedo, and in turn leads to more reflection of solar radiation and even lower temperatures. Milankovitch Cycle - Tilt Obliquity varies from 22.1° to 24.5° (an angle of 2.4°) and back again, over a time period of approximately 41,000 years. In periods with lesser tilt (poles facing away from sun), the tropics get hotter. However, higher latitudes experience winters that are much deeper and colder.

Decreased Tilt + Greater Eccentricity Theoretically, periods with lesser tilt coupled with greater eccentricity may cause very long and deep winters, and which changes albedo dramatically. The increase in reflective ice sheets and glaciers can cause close to 50% of total solar radiation to be reflected and hence temperatures to decrease significantly to usher in ice ages.

This table is COMPLETELY FOR KNOWLEDGE alone, and will never be tested for Geography. Magnets are not magical, but occur when one end of the magnet is charged with positive ions while the other is not. This creates a magnetic field - something like an invisible force that will pull other magnetised things towards it. Some planetary bodies have magnetic fields as well, because some planets have hot cores which cause material within the planet to move. This movement can cause one end of the planet to have a magnetic charge - hence planets like the earth and the sun have magnetic fields. Refer to diagram on the left and This website to find out how sunspots are related to magnetic fields, and how they are related to the solar cycle.

Sunspots are storms on the sun’s surface that are marked by intense magnetic activity. Sunspots are characterised by solar flares and hot gassy ejections from the sun’s corona (upper atmosphere). Scientists believe that the number of spots on the sun cycles over time, reaching a peak—the so-called Solar Maximum—every 11 years or so. During the Solar Maximum - the sun’s output of solar energy increases, and hence so does the total radiation earth receives. Some skeptics of human-induced climate change blame global warming on natural variations in the sun’s output due to sunspots. Even without anthropogenic factors, positive feedback loops will start occurring as long as solar radiation increases. The United Nations’ prestigious Intergovernmental Panel on Climate Change (IPCC)—incorporate the effects of the sun’s solar cycles. However, when you study the graph above, it is evident that solar cycles have a frequency of every 11 years or so, which does not explain the consistently increasing global temperatures of the last 30 years. Also, the solar cycle seems to be on the decreasing limb at the moment - and the number of sunspots is at some of the lowest levels since the 1980s. This is also not congruent with temperature changes on the earth for the last 30 years.

Impacts (Consequences) of Climate Change

Responses to Climate Change International Strategies

International Strategy 1

Kyoto Protocol [UN Framework Convention on Climate Change (UNFCCC)]

Description: Drawn up in Kyoto, Japan on 11 Dec 1997 and came into force on 16 Feb 2005 to reduce levels of greenhouse gases. Countries were obliged to reduce their combined greenhouse gas emissions by at least 5% below their 1990 level from 2008 to 2012. Greater responsibility was placed on 37 developed countries and the European countries as they were mainly responsible for the high levels of greenhouse gas emissions as a result of more than 150 years of industrial activity. Depending on the ability of each developed country, they helped less developed countries=-reduce their greenhouse gas emissions by providing them with funds. Successes: Many countries such as Austria, Finland, Greece, Ireland and Spain met or exceeded targets. Countries monitor and report their greenhouse gas emissions to ensure they are on track in keeping to targets. Successful in encouraging sustainable development. The Clean Development Mechanism (CDM) gave Certified Emission Reduction (CER) credits to countries which carried out emission-reduction projects such as installing energy-efficient infrastructure in less developed countries. Limitations: Countries such as Denmark, Sweden and UK did not achieve their targets. The Kyoto Protocol did not make it compulsory for countries with low greenhouse gas emissions to provide energy-efficient technology to countries with high greenhouse gas emissions. Countries which did not sign the Protocol continued to contribute significantly in the global emissions. Since 1997, global emissions increased by 35%, mainly from China, India and USA

International Strategy 2

Paris Agreement

Description: Latest UNFCCC meeting in 2016. 166 out of 197 countries signed (ratified) an agreement that climate change needs fixing. For the first time brings almost all nations into a common cause to undertake ambitious efforts to combat climate change and adapt to its effects, with enhanced support to assist developing countries to do so. The Paris Agreement’s central aim is to strengthen the global response to the threat of climate change by keeping a global temperature rise this century well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 degrees Celsius. Nationally Determined Contributions (NDCs) – countries now set their own goals to reduce greenhouse gas emissions and results are reported through a global stock take every 5 years. Successes: For the first time, almost all nations, especially the larger economies including the USA, China, and India agreed that climate change is a problem. USA and China initially agreed to lower/limit greenhouse gas emissions. NDCs seem effective since they are bottom up and not top down – nations can balance between developmental needs and climate change. DCs who have industrialised and developed called upon to aid LDCs who have yet to industrialise with green technology. Limitations: Ratification is not really legally binding – the USA under new presidency seems to be pulling out of the agreement, with India following suit. NDCs are difficult for LDCs to follow when developmental needs come first. Climate has already changed and many coastal and polar regions are already seeing massive consequences, so more needs to be done and quicker.

National Strategies Summary Evaluation of Bhutan’s National Strategy Question at Issue Is Carbon Neutrality possible? Purpose Carbon Neutrality or being Carbon negative is possible - as Bhutan demonstrates. Evidence 72% of Bhutan is still under forest cover. Constitution ensures that no less than 60% of Bhutan remains under forest cover. 2.2 million tonnes of CO2 released per year, Bhutan’s forests remove 3 times that amount. Bhutan subsidises public transport so as to reduce the number of private vehicles. Assumptions Hydroelectrical energy is not completely ‘green’, and without environmental consequences. It blocks the flow of water and marine life It can also cause flooding The soil is fertile enough for the growth of forests in most countries. Point of View Bhutan has not contributed to warming, but faces its consequences due to the actions of others. Countries must keep their word, and do their best to follow their promises. Concepts GNH - Gross National Happiness instead of the GDP. Happiness instead of economic growth as the main objective of the country. Gives free electricity to farmers so that they will not burn firewood. The government is trying to go paperless so as to save more trees. Implications Bhutan is a developing, underpopulated country, and it has the land to keep forests because of its low population density. Not all countries are democratic monarchies, and many countries are bipartisan and it is difficult to reach a consensus, e.g Democrats vs Republicans on the issue of climate change If countries are to cover themselves with forest cover, people will be forced into smaller places, causing congestion and overpopulation. Inferences Carbon neutrality and negativity is possible, but the country must sacrifice economic development in order to save the environment. Governments will agree and actually pursue the issue. Countries that are not bipartisan on the issue will likely find it easier to pass these policies.

\ Summary Evaluation of Singapore’s National Strategy Question at Issue Are voluntary contributions to combat Climate Change enough? Purpose Singapore is a prime example of piecemeal, voluntary and slow adoption of climate friendly policies Evidence Singapore Green Plan 2012 Green Mark Scheme Plant a Tree ProgramAssumptions A combination of long-term education and awareness building, together with small incentives for being more ‘Green’ will eventually result in Singapore becoming less carbon positive. Point of View Economic Growth is essential, and is the foundation with which climate change strategies are made possible.

Sample of Strategies from 2000 to 2015: National Strategies Elaboration Evaluation Singapore Green Plan 2012 •Launched in 2002 by the Ministry of the Environment to reduce greenhouse gas emissions by using natural gas as an energy source •To generate 60% of Singapore’s energy needs using natural gas by 2012 as it is a cleaner form of energy compared to coal as it does not produce smoke. Success: •As early as 2010, about 79% of Singapore’s electricity generated from natural gas. Exceeded target ahead of schedule.

Limitations: Complex treatment plants needed to process natural gas High maintenance cost for pipelines as they are laid underground and need to be checked regularly for leakages. Green Mark Scheme •Launched by the Building and Construction Authority (BCA) •Buildings evaluated and certified according to how energy-efficient and environmental friendly they are. Encourage more new ‘green’ buildings which are E.g. buildings which run partly on solar energy. Success: Green Buildings such as Park Royal Hotel, Standard Chartered @ Changi and the National Library reported energy savings of 15% to 35% compared to convention buildings. Reduce greenhouse gas emission as less fossil fuels needed to generate electricity.

Limitations: Not all buildings need to adhere to this scheme. This costs of building these types of buildings are prohibitive and only a small number of building developers will actually chose to build this way. Plant a Tree Program In 2007, a Plant-A-Tree programme was started by the Singapore Environment Council (SEC) and the Garden City Fund. According to a media release on the National Parks Board website, the programme was started in response to tree planting requests from the public to the SEC. The programme enables individuals to plant one or more trees at designated parks or nature reserves on the last Sunday of each month or on special days like the World Environment Day or Earth Day. Success: Aim is to have community actively contribute to tree-planting. Part of the larger program for Green Singapore – to have trees and abundant flora despite being a densely populated city.

Limitations: Token planting for symbolic reasons do not exactly change conditions for carbon neutrality. Year of Climate Action 2018 to today Mitigation: Greening Our Transport Promoting sustainable transport and managing vehicular emissions by promoting cleaner vehicles through emissions standards and encouraging the early replacement of older and more pollutive vehicles such as through the Early Turnover Scheme (switched more than 40,000 commercial diesel vehicles to cleaner vehicles) Land Transport Master Plan 2040 (to be achieved by 2040) 10 peak-period journeys to be made via Walk-Cycle-Ride modes of transport (include public and shared transport) 100% greener, cleaner energy public bus and taxi fleets enhancing existing transport facilities to make them more environmentally-friendly, and designing and building new land transport, airport and port facilities that are sustainable and green, through incorporating energy efficient and carbon mitigation features and technologies.

Adaptation: Protection from floods Source-Pathway-Receptor Approach Source: Places and developments with an area of over 0.2 hectares have to implement measures on-site, such as detention tanks and green roofs, in order to slow down runoff into the public drainage system Pathway: Existing drains are widened and deepened, and diversion canals and centralised detention tanks can be build to capture the large amounts of water from the heavy rain Receptor: Requirements are set for the entrance levels of basements and underground facilities, as well as for the minimum height of the ground level in general. Flood barriers are also set up as part of the ‘receptor’ aspect.

Restoration of Mangroves (Pulau Tekong) Scouring was observed in the past, where swirling water washed away and eroded the mud at the roots of the mangrove trees Soft Engineering Approach: Planting multiple species of native mangrove saplings instead of the traditional method of only planting one species, which would retain the many native species of mangroves Hard Engineering Approach: Installing biodegradable sacks of marine clay in notches formed by erosion, and stones of different sizes along the coast, as well as vigorously tracking the success of these solutions Successes: Tech Singapore aimed to adopt more efficient technologies and increase the share of non fossil fuels in our electricity mix Singapore will develop and demonstrate cutting-edge low carbon technologies as well as scale up low-carbon solutions for deployment in Singapore and export overseas. Introduce smart home technology Allows users to control appliances, making it easier for people to reduce electricity wastage.

Carbon Tax The Government is prepared to spend more than the estimated S$$1 billion in carbon tax revenue collected in the first five years to support projects that reduce carbon emissions. Government plans to raise the carbon tax to $10-$15 The tax would cover for approximately 80% of our national emissions

Impact Since the 2000s, Singapore has progressively switched from fuel oil/diesel to natural gas, a cleaner fuel. Natural gas emits 50 to 60 percent less carbon dioxide (CO2) when combusted. Improvement: Currently, 95% of our electricity is generated from natural gas, up from 26% in 2001. The implementation of energy efficiency projects and good energy management practices not only saves energy, it can also reduce costs for companies. Protection and preservation of our rainforests and mangroves, as well as increasing green spaces allows them to be effective as a carbon sink

Influence At least 80% of our buildings (by floor area) will achieve Green buildings standards by 2030. Increases energy efficiency and enhancing environmental performance Ranked by the International Energy Agency as amongst the top 15 countries best-performing countries in terms of emissions intensity. Due to our sustainability efforts, Singapore’s Carbon Intensity, or carbon dioxide (CO2) emissions per dollar of economic output, is among the lowest in the world. We rank 123rd out of 141 countries, placing us among the 20 best-performing countries.

Limitations:

1. Switching to natural gas    Dangerous - could cause explosions    Processing and frequent maintenance checks on underground pipes require a lot of money, manpower and technology
2. Solar Energy    limited by technological advancements, space constraints and issues with intermittency    for HDB flats, a lot of solar panels are needed to provide enough energy for the whole building, and there is not enough space at the rooftops to install these panels.    it is not effective at times, for example when it rains, cloudy day, etc.
3. Protection of the coast    The Prime Minister mentioned at the National Day Rally last year that climate change adaptation might cost S$100 billion or more over the course of 100 years.    Reclaiming land: geographical limitations and neighbouring countries’ territorial boundaries, it would disrupt the ocean's ecosystem, lead to soil liquefaction, and pollute the water.    Ecological concerns raised over coast protection methods    Most hard engineering techniques, albeit effective, are costly and expensive to maintain

4.. People’s Mindset Even though the schemes might encourage the use of public transport, walk or cycle, they might not think that their actions will not make any difference to our carbon footprint, especially if others do not do the same The government and their implemented schemes are not able to control citizens mindsets and choices, and can only provide suggestions and encourage them to make a change As an industrialised nation, people are reluctant to change their lifestyles and mindsets, especially in consumerism Changing people’s mindset may be hard and takes lots of effort even for a small country like Singapore. It may take too much time and by then it could be too late.

Singapore Green Plan 2030 Description:

The Singapore Green Plan was adopted in 2021, and was in part an update from earlier plans so as to meet Paris Agreement goals. A multi-prong, nation-wide effort to become more sustainable as a nation, and to ultimately reach zero net emissions as soon as possible. This is to be done through: Facilitate efforts to mitigate carbon emissions in all sectors Help Singapore adapt to the effects of climate change Harness economic and green growth opportunities arising from climate change Encourage public awareness and action on climate change More details on how to achieve such an ambitious goal: https://www.greenplan.gov.sg/

Success: Many environmental initiatives were spearheaded by the entire government - such as the Singapore Green Plan, the Green Mark Scheme, Plant-A-Tree, Climate Action 2018. Through Green Plan 2030 Singapore is committed to and will likely reach and exceed the Paris Agreement target of reducing emissions intensity of 36%. This is mostly done by new technologies that allow efficient burning of natural gas and a greater dependency on natural gas (currently 95%). From 2018, increased shifting to alternative energy sources, especially solar energy - rooftops of all public housing to be completely retrofitted with solar panels by 2020, and also plans to lay solar panels on coastal seas in 2019.

Limitations: Singapore is comparatively a tiny nation, and may not have a great impact internationally. Limited resources and land space for alternative energy sources such as geothermal, wind, and nuclear energy. Difficult to balance between the needs of economic development and growth and sustainability.

\