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Ppt of geography, climate change ,water crises
- 1. Climate Change: Fitting the pieces together
- 2. “Greenhouse effect” Increasing greenhouse gases trap more heat
- 3. Greenhouse gases Nitrous oxide Carbon dioxide Methane Water Sulfur hexafluoride
- 6. Sea-level rise projections : a few inches to a few feet •2 ft: U.S. would lose 10,000 square miles •3 ft: Would inundate Miami •Affects erosion, loss of wetlands, freshwater supplies •Half of the world’s population lives along coasts •Big question: Ice sheets
- 8. Produce more fuel-efficient vehicles Reduce vehicle use Improve energy-efficiency in buildings Develop carbon capture and storage processes Triple nuclear power Increase solar power Decrease deforestation/plant forests Improve soil carbon management strategies
- 9. Individual actions Use mass transit, bike, walk, roller skate Buy water-saving appliances and toilets; installing low-flow shower heads. Tune up your furnace Caulk, weather strip, insulate, and replace old windows Unplug appliances or plug into a power strip and switch it off Buy products with a U.S. EPA Energy Star label
- 15. Sewage treatment plant whose effluent is used to create the Wonga Wetlands, Australia. Not only are there 1.1 billion without adequate drinking water, but the United Nations acknowledges 2.6 billion people are without adequate water for sanitation (e.g. wastewater disposal). The issues are coupled, since, without water for sewage disposal, cross-contamination of drinking water by untreated sewage is the chief adverse outcome of inadequate safe water supply. Consequently disease and significant deaths arise from people using contaminated water supplies; these effects are particularly pronounced for children in underdeveloped countries, where 3900 children per day die of diarrhea alone[9]. While these deaths are generally considered preventable, the situation is considerably more complex, since the Earth is beyond its carrying capacity with respect to available fresh water[10]. Often technology is advanced as a panacea, but the costs of technology presently exclude a number of countries from availing themselves of these solutions. If lesser developed countries acquire more wealth, partial mitigation will occur, but sustainable solutions must involve each region in balancing population to water resource and in managing water resources more optimally. In any case the finite nature of the water resource must be acknowledged if the world is to achieve a better balance.
- 16. MADE BY: •AAYUSH JAIN SETHIA •MANISH SHARMA •BHAVAY NAGPAL •KARTIK GOYAL
Editor's Notes
- The topic of climate change is like a puzzle with many different pieces—oceans, the atmosphere, ecosystems, polar ice, natural and human influences. Scientists have been working on this puzzle for more than a century, and while there are still gaps in our knowledge, most experts feel we have the puzzle is complete enough to show that human activities are having an adverse effect on our planet. This talks looks at many of those puzzle pieces, the evidence behind them, and the conclusions we can draw from them.
- [Image 1] Earth’s surface absorbs heat from the sun and then re-radiates it back into the atmosphere and to space. [click, Image 2] Much of this heat is absorbed by greenhouse gases, which then send the heat back to the surface, to other greenhouse gas molecules, or out to space. Though only 1% of atmospheric gases are greenhouse gases, they are extremely powerful heat trappers. By burning fossil fuels faster and faster, humans are effectively piling on more blankets, heating the planet so much and so quickly that it’s hard for Mother Nature and human societies to adapt.
- While there are many substances that act as greenhouse gases, two of the most important are water and carbon dioxide, or CO2.
- [Image 1] CO2 comes from a variety of sources. For example, plants take up carbon dioxide in the air to make wood, stems, and leaves, and then release it back into the air when the leaves fall or the plants die. The concern today is that fossil fuel use is putting huge amounts of CO2 in the atmosphere at a rate faster than the climate system can adapt to.[click, Image 2] In addition, the warming resulting from CO2 and other greenhouse gases also has the effect of increasing evaporation. This adds water vapor to the atmosphere as well. Water vapor is the most important gas in the natural greenhouse effect, contributing 60% of the effect to carbon dioxide’s 26%. And in fact, satellites have detected an increase in atmospheric moisture over the oceans at a rate of 4% per degree F of warming (7% per degree C) since 1988. This additional water vapor amplifies the warming effect.
- Increased warmth has also affected living things. For example, the Japanese keep very detailed records on the blossoming of their Tokyo cherry trees, so they know they are blooming 5 days earlier on average than they were 50 years ago. Also mosquitoes, birds, and insects are moving north in the Northern Hemisphere.
- The oceans will continue their rise in the coming century. The IPCC’s best estimates range from a few inches to a few feet by 2100. If the rise is 2 feet, the US could lose 10,000 square miles, If they rise three, they will inundate Miami and most of coastal Florida. Sea-level rise also increases coastal erosion and the loss of coastal wetlands, and saltwater spoils freshwater drinking supplies. Coastal populations become even more vulnerable to storm surge and flooding. Considering that half of the world’s population lives near coasts, sea-level rise is a serious concern.The big unknown in all this is how much the planet’s ice sheets will melt.
- [Image 1] A warming planet means continuing changes in its ecosystems. As the oceans absorb more carbon dioxide, the chemistry of the ocean changes, putting many sea creatures at risk. The IPCC projects that by 2100 the pH of the ocean will drop to its lowest point in at least 20 million years. [click, Image 2] As temperatures get milder, mosquitoes, ticks, rodents, and other disease carriers will expand their range, particularly in developing countries. Here in the U.S., dengue hemorrhagic fever, a tropical, mosquito-borne disease, hit for the first time in modern times in 2005 in the Lower Rio Grande Valley. [click, Image 3] Warmer temperatures will also mean less snow overall at certain latitudes because more will fall as rain, and the snow that does fall will melt faster. This affects people living in areas that depend on snow-fed reservoirs for water. [click, Image 4] The IPCC projects increases of 5-20% in crop yields in the first decades of this century. but the crops will be more prone to failure if climate variability increases and precipitation becomes less dependable. And ironically, with higher temperatures comes an increased potential for killing freezes. This is because plants start growing earlier, making them more vulnerable to sudden spring-time cold spells.
- Here are examples of 8 technologies that could save 8 billion tons, or 8 wedges, of carbon. Some of these we could do right away, while others are based on technologies still being studied, such as capturing and storing carbon.[Details on strategies:Efficient vehicles: Double car fuel efficiency in 2055 from 30 miles per gallon (mpg) to 60 mpgReduced vehicle use: Halve the miles traveled by the world’s cars in 2055Efficient buildings: Cut emissions by 25% in all buildingsCCS electricity: Capture and store carbon from 800 large coal power plants or 1600 large natural gas power plantsTriple the world’s current nuclear capacitySolar electricity: Increase solar capacity 700 times Forest storage: Halve global deforestation and double forest planting in 50 yearsSoil storage: Apply carbon management strategies to all of the world’s farm fields]This list represents only some of the possible strategies, but choosing strategies will not be easy. However, the longer we wait to reduce emissions, the higher the target will need to be, and the more adaptation will be necessary. In 2004, when the wedges concept was first introduced, the target was only 7 billion tons.
- As you can see, there are many ways society can approach the struggle to reduce carbon emissions, but there is no single solution. Many of the strategies mentioned are the realm of governments. And the ever-growing world population means that we’ll have to work that much harder to reduce global emissions. But on an individual level, there are many things you can do to make a difference.[click to reveal examples]Lots of other ideas are available on the Internet.
- Scientists are still working on the puzzle. The IPCC’s 5th Assessment Report is planned for 2013-2014. Climate models are being improved, more data is being collected. However, the puzzle is already complete enough to know we need to take action.