Climate Change - The Science • https://www.youtube.com/watch?v=DOAqECd70Ww • Energy travels through a vacuum between the sun and the earth by means of electromagnetic radiation or light. Objects can absorb energy from the light and can emit light energy[if the vibrations of their chemical bonds generate oscillations of the electrical field]. • The temperature of the surface of the earth is controlled by the ways that energy comes in from the sun and shines back out to space as infra-red. Sunlight strikes the earth and deposit some its energy on earth. The account of the energy that enters the earth and leaves the earth is known as the energy balance of the earth.

• The earth’s energy budget is the net result of a complex balance of energy flows over time, and exerts a primary influence on global climate. Earths Energy Balance Energy Balance • Less than half of the incoming sunlight heats the earth. The rest is reflected away by white clouds/ice or gets absorbed by the atmosphere. The sunlight that makes it to the ground warms the earth surface. • Light from the sun is absorbed by land, water, and vegetation on the surface of the earth and give off infrared –which we feel as heat. The infrared radiation or heat moves back up through the atmosphere. • In the atmosphere, green house gases prevent the heat from leaving as fast as they came in. • .Green house gases in the earth’s atmosphere contains molecules that absorb this heat and reradiate the heat in all directions. These greenhouse gases have a molecular structure made up of more than two component atoms that are able to vibrate with the absorption of heat. • Eventually, a vibrating molecule emits the radiation again, which is often reabsorbed by yet another greenhouse gas molecule. The absorption-emission- absorption cycle that occurs among greenhouse gases effectively holds heat in the atmosphere near the earth’s surface, just as clear glass walls hold heat in a greenhouse, thereby slowing the process of heat being lost into space.

Climate Change. • Without the greenhouse effect, the mean surface temperature of the earth would be about 33 degrees Celsius lower than it is today, and most of the world’s oceans would freeze over. • Greenhouse gas molecules are responsible for the fact that the earth enjoys temperatures suitable for life as we know it in our complex biosphere. • Examples of green house gases include carbon dioxide, various halocarbons, methane, nitrogen oxides, nonmethane volatile organic compounds such as benzene, ethanol; ozone, sulfur hexafluoride, and water vapor • Water vapor is the most abundant and dominant greenhouse gas in the atmosphere but due to the anthropogenic source and the rising concentration in the atmosphere, carbon dioxide receive more attention. Carbon Cycle • All living things are made of elements, the most abundant of which are, oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorous. • Of these, carbon is the best at joining with other elements to form compounds necessary for life, such as sugars, starches, fats, and proteins. Together, all these forms of carbon account for approximately half of the total dry mass of living things.- “carbon-based life forms”-Star Trek. • Carbon is also present in the Earth's atmosphere, soils, oceans, and crust. These components can be referred to as carbon pools (sometimes also called stocks or reservoirs) because they act as storage houses for large amounts of carbon. • Any movement of carbon between these reservoirs is called a flux. • In the earth system, fluxes connect reservoirs together to create cycles and feedbacks. An example of such a cycle is; carbon in the atmosphere is used in photosynthesis to create new plant material. This processes transfers large amounts of carbon from one pool (the atmosphere) to another (plants). Over time, these plants die and decay, are harvested by humans, or are burned (fossil fuels) either for energy or in wildfires. • Carbon cycle refers to the flow of carbon among the various reservoirs of carbon. • The carbon cycle plays a key role in regulating the Earth’s climate by controlling the concentration of carbon dioxide in the atmosphere Carbon Cycle Carbon Cycle • Atmospheric carbon dioxide levels have been measured continuously since 1958. Charles Keeling measurements produced what is referred to as the Keeling Curve. The keeling curve shows the change in CO2 content with time. The keeling curve show two interesting features:

i. Every year CO2 concentration reaches a maximum in May and then decreases until October and then it begins to rise. This is due to cycle of plant growth and death in the northern hemisphere.

ii. The second feature of the Keeling curve is that atmospheric CO2 content has been rising rapidly. • Approximately 3.3 of the 6.3 billion metric tons (gigatons) of anthropogenic carbon fail to be taken up by the other reservoirs each year, and add to the accumulated stock of carbon (and other greenhouse gases) in the atmosphere. • Every 2.1 gigatons of carbon-equivalent emissions (net of what is taken up by the earth’s carbon sinks) results in a 1 ppm (part per million) increase in atmospheric carbon dioxide concentrations.

• It is this progressive rise in atmospheric greenhouse gas concentrations, caused by anthropogenic emissions in excess of the earth’s capacity for uptake and sequestration, that results in a climate forcing: Mechanism that alters the global energy balance Economics of Climate Change • The Problem: Climate change is a global public bad; market failure. Any action taken to moderate climate change provides a global public good, implying the strong possibility of free-rider actions. • Why does the market fail to provide the socially desirable level of climate protection? We demonstrated why the market fails to provide the socially desirable level of public good.- revision! • Global public ‘bads’ exist when no market has emerged to provide protection because everyone benefits from one person’s actions: non-excludability and non- rivalry in consumption. • Economics treat climate change as the classic example of global stock externality. • We distinguish between a stock and a flow pollutant. Stock pollutant is concentration- the accumulated carbon in the atmosphere like water ins a bathtub. Flow pollutant is the emission; the annual rate of emission like water flowing into a tub. • Climate change is the effect from the global carbon stock. The concentration of the green house gases give rise to climate change. • This makes dealing with climate change very tricky because changes in any one year’s emission have trivial effect on the current overall concentrations and for that matter, the effect on climate change. • The public good nature of climate change implies that it is the sum of all the carbon emitted around the globe that matters; all climate protection is non-rival and non- excludable. This is crucial for any solution to dealing with climate change. Today the industrialized world contribute the largest portion of emissions but soon developing countries like China and India would be the largest emitters. International cooperation is the key to effective abatement. Analyzing the Cost and Benefits of Climate Change. • We define the cost of climate change as what society has to forgo to pursue climate policy. • Benefit refers to the gains from reducing climate change risks by lowering emissions or enhancing the capacity for adaptation. The benefits of climate protection can be categorized into four four broad sets: • 1. Avoided losses to market goods and services such as the effect of drought on farming outputs, less potable water etc • 2. Avoided losses on non-market goods such as coastal areas, less biodiversity etc • 3. Catastrophes such as hurricanes, frequent outbreaks of infectious diseases such as cholera, malaria, zika etc. • 4. Effects from less use of fossil fuels such as less air pollution.

• Estimate of the impact of climate change on the world GDP ranges between 1% and 2 % Costs and Benefits of Climate Protecon • Estimates of climate protection costs range from modest of -0.5% to -3% loss of global GDP . The Clinton Administration estimated that it will cost the US about less than 0.5% ($10 billion) drop in annual GDP to meet emission targets; 5% rise in gasoline prices, lower electricity rates, no major impact of employment rate.

• Other studies suggests that US GDP can take an annual hit of nearly 3%, trade deficit would increase by billions, gasoline price would increase by 50% and electricity prices would nearly double 2 million US jobs would disappear. The global cost have been estimated at over $700 billion; US bearing about two-thirds of it. Creang Economic Incenves to Deal with Climate Change • Economic incentives can deal with climate change problem by creating a market price for carbon which is otherwise treated as a free good. This price would create a tangible financial reason to reduce carbon emissions and provides the means to do so at low cost. • Taxes and Tradable permits trading are two such tools. People respond to these new prices by switching to less-carbon intensive alternatives, increase energy efficiency per unit of output by using less energy intensive technologies, adoption technologies to reduce emissions, reducing the production of high-cost, carbon intensive goods, increasing sequestration of carbon; developing and refining new technologies. • Carbon taxes work by taxing fossil fuels. Taxing fossil fuels work because their carbon content is easily ascertained. • Emission trading allows regulated emitters to buy emission reduction efforts from other emitters; in effect, contracting other emitters whose abatement costs are less than their own to make reductions for them. Internaonal Cooperaon on Climate Change • The free rider incentive of climate protection cause emissions to be abnormally high, but they also inhibit investment in research and development, a key ingredient in promoting innovative, low-carbon technologies. • Free-rider effects also inhibit the participation of nations in the climate change agreements that are designed to correct this market failures. To further complicate matters, the damage caused by greenhouse pollutants is an externality in both space and time. • Spatially, the largest emitters (the industrialized nations) have the greatest capacity to reduce emissions, but they are not expected to experience as much damage from insufficient actions as the developing countries. • Temporally, the costs of controlling greenhouse gases fall on current generations, while the benefits from controlling them occur well into the future, making it more difficult to convince members of the current generation to join the mitigation effort. • The implication of these insights is that decentralized actions by markets and individual governments are likely to violate both the efficiency and sustainability argument. International collective action is both necessary and terribly difficult. Negoaons over Climate Change Policy • The focus of many climate change negotiations is cost- effectiveness. • The policy choices is always between emission charges and cap- and-trade. Europe favor carbon taxes an d US favored cap-and trade. • Europe and other countries argue that designing carbon tax could be simple and cost effective. Imposing a uniform per-unit charge imposed on all emission sources could encourage new and more more environmentally benign technologies, but also to raise significant revenue. In addition, the use of taxes could assure more stable carbon prices. But concerns was raised about what the revenue from the taxes will be used for and the financial burden it put on industries. • Most international agreements now focus more on cap-and-trade. Kyoto Protocol • The Kyoto Protocol was an agreement by industrial countries with economies in transitions mostly the soviet union to a legally binding emissions targets in December 1997 at a conference in Kyoto, Japan. • The protocol became effective in February 2005 with 55 countries ratifying it. • The Kyoto Protocol defines a five-year commitment period (2008–2012) for meeting the individual country emissions targets, called Assigned Amount Obligations. • Quantified country targets are defined by multiplying the country’s 1990 emissions level by a reduction factor and multiplying that number by 5 (to cover the five-year commitment period). • The individual country targets would represent a 5 percent reduction in annual average emissions below 1990 levels for the participating parties collectively. • The actual compliance target is defined as a weighted average of six greenhouse gases: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride. • The Kyoto Protocol authorizes three cooperative implementation mechanisms that involve tradable allowances: Emission Trading, Joint Implementation, and the Clean Development Mechanism (CDM). • Emissions Trading ( a cap-and-trade policy) allows trading of assigned amounts among the industrialized nations and the economies in transition. • Under “Joint Implementation” (JI), Parties can receive emissions reduction credit when they help to finance specific projects that reduce net emissions in another . This project- based program is designed to exploit opportunities in countries that have not yet become fully eligible to engage in the emission trading program. Kyoto Protocol • The Clean Development Mechanism enables industrialized countries to finance emissions reduction projects in developing and receive certified emissions reductions (CERs) for doing so. These CERs can be used to fulfill assigned amount obligations. • The CDM provides a means for motivating industrialized countries (or individual companies) to invest in projects in developing countries that result in reductions of greenhouse gases. The incentive to invest is provided by the fact that investors can receive credit for the reductions that are “additional” to reductions that would have been achieved otherwise. Once verified and certified, these credits can then be used as one means of meeting the investor’s “assigned amount” obligation. • The United States have not signed this agreement officially but

some states have accepted mandatory caps on CO2. The European Union implemented the largest cap-and-trade system to meet the Kyoto protocol The Paris Agreement • The objective of the Paris Agreement(PA) was defined in terms of the warming of the earth. The PA objective is to hold the increase in the global average temperature to below 2 oC above pre-industrial revolution level with even some countries like US, China supporting an increase below 1.5 oC. • To keep warming below 1.5 degrees by 2100, the world must stop emitting green house gases into the atmosphere by 2060 and must start pulling carbon from the atmosphere afterwards. There disagreements on how this can be achieved. • The PA deals with this by requiring countries to peak global green house gas emissions as soon as possible and after 2050 all anthropogenic emissions should be balanced with “removal by sinks”-essentially through technology and afforestation. • In order to get developing countries to commit to this agreement, there was a provision that was agreed by the US, Canada and other industrial countries to provide a financial support of 100 billion annually by 2020 to developing countries to help them adapt to current impacts of climate change that is largely caused by industries and technology that will help developing countries to meet the target under the PA. Problems with Internaonal Agreements

• Monitoring and Evaluations

• Domestic Politics.

• Developmental challenges with implementation.