Climate changes Prof. RNDr. Milan Viturka, CSc. FEA MU, Brno What is Global Warming and Climate Change? Global warming refer to an increase in average global temperatures. Natural events and human activities are believed to be contributing to an increase in average global temperatures. This is caused primarily by increases in "greenhouse „ gases. A warming planet thus leads to a change in climate which can affect weather in various ways. What are the main indicators of Climate Change? As explained by the US agency “National Oceanic and Atmospheric Administration„ there are seven indicators that would be expected to increase in a warming world and three indicators would be expected to decrease: The indicators for a global warming What is the Greenhouse Effect? The term greenhouse is used in conjunction with the phenomenon known as the greenhouse effect Øenergy from the sun drives the earth’s weather and climate, and heats the earth’s surface Øin turn, the earth radiates energy back into space Øsix main greenhouse gases and water vapour trap some of the outgoing energy, retaining heat somewhat like the glass panels of a greenhouse Øthe result is the rise in temperature on Earth as certain gases in the atmosphere trap energy. Øsix main greenhouse gases are: carbon dioxide/CO2, methane/CH4 (which is 20 times potent as CO2) and nitrous oxide/N2O plus three fluorinated industrial gases i. e. hydrofluorocarbons/HFCs, perfluorocarbons/PFCs) and sulphur hexafluoride/SF6 This is a necessary sign that the greenhouse effect is a prerequisite for life on Earth - without their effect, the average temperature at the Earth's surface (determined only by the radiation balance) was -18 ° C. Human impact on climate change Human activity has caused an imbalance in the natural cycle of the greenhouse effect and related processes. •when we mine coal and extract oil from the Earth’s crust, and then burn these fossil fuels for transportation, heating, cooking, electricity and manufacturing, we are effectively moving carbon into the atmosphere than is being removed naturally through the sedimentation of carbon. •by clearing forests to support agriculture, we are transferring carbon from living biomass into the atmosphere (dry wood is about 50 percent carbon). •if the greenhouse effect becomes stronger, then more heat gets trapped than needed, and the Earth might become less habitable for humans, plants and animals. •the difference between the natural carbon cycle and human-induced climate change is that the latter is rapid and ecosystems have less chance of adapting to the changes. The result is that humans are adding ever-increasing amounts of extra carbon dioxide into the atmosphere. Because of this, atmospheric carbon dioxide concentrations are higher today than they have been over the last half-million years or longer. Main indicators C:\Users\Milan\Documents\Climate\Climate Change Affects Biodiversity — Global Issues_soubory\ocean-acidification.jpg Ecosystem Impacts Many studies have pointed out that the rates of extinction of animal and plant species, and the temperature changes around the world since the industrial revolution have been significantly different to normal expectations. Those observations note that global climate changes will lead to the following situations: vrapid global warming vdramatic increase in greenhouse gas emissions vwarming of the oceans leads to further increase greenhouse gasses vpermafrost thawing will aggravate global warming vinduced massive extinction of species deepens the environmental crisis vsuch vicious circle where each problem exacerbate other problems can lead to a sudden collapse of biological and ecological systems veffective measures can decrease global warming and other problems, unfortunately the world community has repeatedly failed to establish cooperation in this . Other impacts ürising sea levels - affecting many small islands and a large mass of humanity lives near the coasts or by major rivers üincreasing ocean acidification - resulting changes in the chemistry of the oceans disrupts the liveability of plants and animals in the sea üincrease in pests and disease - climate changes can increase pathogen development, disease transmission and host susceptibility üfailing agricultural output, increase in world hunger - drought and desertification are starting to spread and, intensify in some parts of the world already üagriculture and livelihoods are already being affected - most noticeably in the tropics and subtropics üchanging crops - in some cases, improved agricultural techniques may help, such as rainwater harvesting and drip irrigation (some also believe may be essential to deal with changing climate). The climate has always varied in the past. How is this any different? Throughout Earth’s history the climate has varied, sometimes considerably. Past warming does not automatically mean that today’s warming is therefore also natural. Recent warming has been shown to be due to human industrialization processes. Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities since 1750. The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land-use change, while those of methane and nitrous oxide are primarily due to agriculture. There is a huge contrast between developed and developing countries. In terms of historical emissions, industrialized countries account for roughly 80% of the carbon dioxide. Much of the growth in emissions in developing countries results from the provision of basic human needs for growing populations, while emissions in industrialized countries contribute to growth in a standard of living. This is exemplified by the large contrasts in per capita carbons emissions between industrialized and developing countries (per capita emissions of carbon in the U.S. are over 20 times higher than India); around 2007, China surpassed the US as the world’s largest emitter. Development of emission of CO2 Textové pole: At the 1997 Kyoto Conference, industrialized countries were committed to an overall reduction of emissions of greenhouse gases to 5.2% below 1990 levels for the period 2008—2012. The set targets were not met - overall global GHG emissions increased by 11% over the reference period. At the 1997 Kyoto Conference, industrialized countries were committed to an overall reduction of emissions of greenhouse gases to 5.2% below 1990 levels for the period 2008—2012. The set targets were not met - overall global GHG emissions increased by 11% over the reference period. Prediction of climate change . Heat maps The Intergovernmental Panel on Climate Change predicts that temperatures are most likely to rise by 1,8 ° C – 4 ° C by 2100. But the possible range is much greater; 1,1 °C – 6,4 ° C. The maps above show how a range of three different scenarios will affect different parts of the planet. The emissions scenarios, A1B, A2, B1, used to create the maps above, are based on a range of detailed economic and technological data. These versions of the future consider different population increases, fossil and alternative fuel use, and consequent CO2 increases. Ozon depletion and extinction Global warming also contributing to ozone depletion due to the associated cooling of stratosphere. So called ozone hole consists since the late 1970s especially around Earth's polar regions. The main cause of ozone depletion and the ozone hole is manufactured chemicals, especially chlorofluorocarbons (CFCs) and halons (HCFCs). They release atoms from ozone and breakdown it into oxygen. Ozone depletion and the ozone hole have generated worldwide concern over increased cancer risks and other negative effects. The ozone layer prevents most harmful wavelengths of ultraviolet (UV) light from passing through the Earth's atmosphere. These wavelengths cause skin cancer, blindness as well as harming plants and animals. These concerns led to the adoption of the Montreal Protocol in 1987, which bans the production of CFCs, halons, and other ozone-depleting chemicals. Ozone levels than stabilized by the mid-1990s and began to recover in the 2000s. Recovery is projected to continue over the 21. century, and the ozone hole is expected to reach pre-1980 levels by around 2075. The Montreal Protocol is considered the most successful international environmental agreement to date. World map of the Global climate risk index 1996–2015 Countries most affected by extreme weather events (1996–2015) 1 Honduras 2 Myanmar 3 Haiti 4 Nicaragua 5 Philippines 6 Bangladesh 7 Pakistan 8 Vietnam 9 Guatemala 10 Thailand Top 10 warmest years (1880–2020). Rank 1 = warmest period of record Year Anomaly °C 1 2016 0.65 2 (tie) 2020 0.64 2 (tie) 2019 0.64 4 (tie) 2015 0.64 5 (tie) 2017 0.64 5 (tie) 2018 0.62 7 (tie) 2014 0.62 8 (tie) 2010 0.58 9 (tie) 2013 0.58 10 2005 0.59 Scepticism on global warming or that it can be human-induced For a very long time, something of contention and debate in the U.S. had been whether or not a lot of climate change has in fact been induced by human activities, while many scientists around the world, Europe especially, have been more convinced that this is the case. Famous American writer Mark Twain might as well have been talking about global warming when he famously remarked, “Everybody talks about the weather, but nobody ever does anything about it.” For years we have heard so much about the causes of climate change, that we’ve missed the fact that there are simple, practical solutions that can slow this growing problem. Technologies exist today that can cut emissions of heat trapping gases and make a real difference in the health of our planet. And these solutions will be good for our economy, reduce our dependence on foreign oil and enhance our energy security. Union of Concerned Scientist. Challenge We Can Meet Global warming doesn’t just mean balmy February days in northern climes. It also means increasingly hot days in the summer, and a host of negative impacts that are already under way and are expected to intensify in the coming decades. qMore heat waves will likely increase the risk of heat-related illnesses and deaths. qCities and towns along the nation’s major rivers will experience more severe and frequent floodings. qSome areas will likely experience more extensive and prolonged droughts. qSome of our favorite coastal and low-lying vacation areas, such as parts of the Florida Keys, will be much less appealing as sea levels rise, dunes erode, and the areas become more vulnerable to coastal storms. qMany families and businesses, who have made their living from fishing, farming, and tourism could lose their livelihoods, and others who love hunting, boating, skiing, birdwatching, and just relaxing near lakes, streams and wetlands will see some of their favorite places irretrievably changed. § § § Comprehensive ideas for solving the problem of global warming Reduce fossil fuel use Burning fossil fuels increases the levels of greenhouse gases in the atmosphere. There are two ways to reduce fossil fuel use: Use less energy or use alternative energy sources like solar and wind power. Plant trees Plants take in carbon dioxide and release oxygen. They use carbon to build their own tissues and return some of it to the soil in a process called sequestration. Deforestation of rain forests is a large contributor to global warming but planting new trees and help to offset this. Reduce waste The production of waste contributes to global warming both directly and indirectly. Decomposing waste produces methane and other greenhouse gases. Recycling metal, plastic, glass and paper lowers greenhouse gas emissions, since recycled items take far less energy . Conserve water Cities consume significant amounts of energy when purifying and distributing water, which contributes to greenhouse gas emissions. Saving water reduces the amount of energy used. How each of us can contribute to this Øsaving electricity by using energy-efficient appliances and compact fluorescent light bulbs, as well as reducing gasoline use and buying green power from your electricity provider, if available. Øreducing your consumption patterns and reusing items whenever possible minimizes your carbon footprint, since fewer new items need to be made Øturn off water immediately whenever you're not using it, and repair or replace leaky faucets and toilets. In your yard, landscape with plants and grasses that require less water, and capture rainwater in barrels for irrigating. Ø Ø Ø braz_defor_88-05-lrg satelitní snímky (1989) a (2014) zachycují rychlé vysychání jezera. Rozsáhlé světleji zbarvené plochy v okolí jsou solné pláně na místech vyschlého dna. Aral lake: situation in 1989 and 2014 Thanks for your attention