Module 1 Intro to Climate Change PDF
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This document introduces climate change, differentiating between weather and climate. It details the components of the climate system and the significance of its variability. The document is likely part of a course on environmental science or global issues.
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INTRODUCTION Climate change is a major global problem that affects everything in our lives. It's mainly caused by what humans do, like releasing gases that trap heat in the air. This messes up the Earth's climate. Learning about climate change is important because it helps people understand it and...
INTRODUCTION Climate change is a major global problem that affects everything in our lives. It's mainly caused by what humans do, like releasing gases that trap heat in the air. This messes up the Earth's climate. Learning about climate change is important because it helps people understand it and take action to fix it. According to a 2017 report of the United States Agency on International Development (USAID), the Philippines is highly vulnerable to the impacts of climate change, including sea level rise, increased frequency of extreme weather events, rising temperatures and extreme rainfall. The country relies on climate-sensitive natural resources and most of the population resides in major cities along coastlines. In addition, the country lies in the world’s most cyclone- prone region and sea level rises faster than the global average. This module is meant to give a complete overview of climate change, including what causes it, how it affects us and what we can do to solve it. COURSE OBJECTIVES After this course, the students should be able to: 1. Explain the science of Climate Change and its impacts. 2. Assess disaster risk. 3. Develop risk reduction strategies. 4. Evaluate disaster preparedness plans. 5. Apply effective communication strategies for disaster risk management. 6. Analyze the role of different stakeholders in disaster risk management. 7. Advocate for climate change mitigation and adaptation strategies. I. INTRODUCTION TO CLIMATE CHANGE A. WEATHER AND CLIMATE Weather and climate have a profound influence on life on Earth. They are part of the daily experience of human beings and are essential for health, food production and well-being. Many consider the prospect of human-induced climate change as a matter of concern. Weather and climate are two related concepts that describe different aspects of the Earth's atmosphere. Weather refers to the condition of the atmosphere at a particular time and place. It includes short-term changes in temperature, humidity, wind, rain, clouds and other atmospheric phenomena. Weather can change quickly within hours or days and can vary from one location to another. For example: a sunny day, a rainy afternoon, or the passage of a cold front. Climate refers to the long-term average of weather conditions observed in a specific region, typically over at least 30 years or more. It encompasses the patterns, trends and variations in temperature, precipitation, humidity and atmospheric circulation over an extended period. Climate gives a broader perspective by looking at the usual weather patterns, seasonal variations, and historical climate trends of a particular area. It is often described based on average temperatures, rainfall patterns and other factors that influence the overall climate conditions. Table 1. Key Differences Between Weather and Climate Difference Weather Climate Short-term, usually observed Long-term averages and patterns, Time Frame over minutes to days typically over 30 years or more Describes immediate and specific atmospheric Describes the typical weather phenomena such as Scope patterns and trends of a region temperature, humidity, over an extended period precipitation, and wind on a given day Can change rapidly and Reflects the overall, more stable Variability unpredictably trends and averages Measured using current data from meteorological Analyzed through long-term data Measurement instruments, including records and statistical average of temperature sensors, weather observations barometers, and radar Affects daily activities and Influences broader, long-term Impact immediate decisions planning and adaptation Provides a general understanding Forecasts are generally of what to expect over many accurate for a few days to a Predictability years, useful for long-term week, but less reliable over strategies and understanding longer periods trends While weather and climate are separate concepts, they are interconnected. Weather patterns and events contribute to long-term climate trends, and understanding past and current weather conditions is crucial for analyzing and predicting climate patterns. Climate change, for example, refers to shifts in long-term weather patterns and trends influenced by factors like greenhouse gas emissions and human activities. B. CLIMATE SYSTEMS Climate systems refer to the complex and interconnected processes that determine the climate of a particular region or the Earth as a whole. These systems involve various components that interact with each other to produce the characteristic patterns of temperature, precipitation, wind, and other climatic factors. Figure 1. The components of the climate system, their processes, and interactions. This includes the atmosphere, biosphere (life), cryosphere (ice), hydrosphere (water), land and human influences, and the interactions between these components (shown with two-way arrows). The parts of the system that can change are labeled as "Changes". Source: https://scied.ucar.edu/learning-zone/earth-system/climate-system Components of Climate System 1. The atmosphere is the most unstable and rapidly changing part of the system. The Earth’s dry atmosphere is composed mainly of nitrogen (N2, 78.1% volume mixing ratio), oxygen (O2, 20.9% volume mixing ratio, and argon (Ar, 0.93% volume mixing ratio). The atmosphere contains water vapor (H2O), which is also a natural greenhouse gas. 2. The hydrosphere is the component comprising all liquid surface and subterranean water, both freshwater, including rivers, lakes and aquifers, and saline water of the oceans and seas. The oceans cover approximately 70% of the Earth’s surface. They store and transport a large amount of energy and dissolve and store great quantities of carbon dioxide. 3. The cryosphere, including the ice sheets of Greenland and Antarctica, continental glaciers and snow fields, sea ice and permafrost, derives its importance to the climate system from its high reflectivity (albedo) for solar radiation, its low thermal conductivity, its large thermal inertia and, especially, its critical role in driving deep ocean water circulation. 4. Vegetation and soils at the land surface (lithosphere) control how energy received from the Sun is returned to the atmosphere. Some is returned as long-wave (infrared) radiation, heating the atmosphere as the land surface warms. Some serves to evaporate water, either in the soil or in the leaves of plants, bringing water back into the atmosphere. 5. The marine and terrestrial biospheres have a major impact on the atmosphere’s composition. The biota influences the uptake and release of greenhouse gases. Through the photosynthetic process, both marine and terrestrial plants (especially forests) store significant amounts of carbon from carbon dioxide. ACTIVITY 1: Draw a map incorporating the 5 components of the climate system (individual). Medium: Traditional Visual or Digital (Any) Bond Paper (preferably A4-size), portrait Top part – drawing; bottom part – explanation of the drawing Criteria: Accuracy of Content -------- 30% Comprehensiveness -------- 30 % Creativity ----------------------- 25% Visual appeal ----------------- 15% TOTAL -------------------------- 100% DEADLINE: September 19, 2024, 5PM C. CLIMATE VARIABILITY IN THE PHILIPPINES The Climate of the Philippines is tropical and maritime. It is characterized by relatively high temperature, high humidity and abundant rainfall. It is similar in many respects to the climate of the countries of Central America. Temperature, humidity, and rainfall, which are discussed hereunder, are the most important elements of the country's weather and climate. 1. General Climate Characteristics Type: Tropical maritime. Temperature: Generally warm throughout the year, with average temperatures ranging from about 25°C to 32°C (77°F to 89°F). Coastal areas tend to be warmer and more humid, while mountainous regions can be cooler. The coolest months fall in January while the warmest month occurs in May. The difference between the mean annual temperature of the southernmost station in Zamboanga and that of the northernmost station in Laoag is insignificant. In other words, there is essentially no difference in the mean annual temperature of places in Luzon, Visayas or Mindanao measured at or near sea level. Humidity: Due to high temperature and the surrounding bodies of water, the Philippines has a high relative humidity. The average monthly relative humidty varies between 71 percent in March and 85 percent in September. The combination of warm temperature and high relative and absolute humidities give rise to high sensible temperature throughout the archipelago. It is especially uncomfortable during March to May, when temperature and humidity attain their maximum levels. Rainfall: Rainfall is the most important climatic element in the Philippines. Rainfall distribution throughout the country varies from one region to another, depending upon the direction of the moisture-bearing winds and the location of the mountain systems. The mean annual rainfall of the Philippines varies from 965 to 4,064 millimeters annually. Baguio City, eastern Samar, and eastern Surigao receive the greatest amount of rainfall while the southern portion of Cotabato receives the least amount of rain. At General Santos City in Cotabato, the average annual rainfall is only 978 millimeters. 2. Seasonal Patterns Wet Season: o Timing: June to November. o Monsoons: Dominated by the southwest monsoon (Habagat), which brings heavy rainfall and high humidity. o Typhoons: This period is also the typhoon season, with the highest frequency of typhoons occurring from July to October. Typhoons can cause significant rainfall and storm surges, impacting many parts of the country. Dry Season: o Timing: December to May. o Monsoons: Influenced by the northeast monsoon (Amihan) which brings cooler and drier air. Sub-Periods: o Cool Dry Season: December to February, with lower temperatures and lower humidity. o Hot Dry Season: March to May, characterized by higher temperatures and increased heat. 3. Regional Variations Northern Luzon: This region, including the Batanes and northern parts of Luzon, experiences cooler temperatures and more pronounced seasonal variations. It is also more prone to typhoons. Central Luzon and Metro Manila: Typically experiences a more pronounced wet and dry season with a more consistent temperature range. Southern Luzon and the Visayas: Generally has a more evenly distributed rainfall throughout the year, with less pronounced dry seasons. Mindanao: Usually receives more evenly distributed rainfall throughout the year and has a less pronounced dry season compared to other parts of the Philippines. 4. Climatic Types The Philippines can be divided into several climatic types based on rainfall patterns and seasonal variations: Type Description Example Areas Type I Two distinct seasons: a wet Metro Manila and most of season from May to October Western Luzon and a dry season from November to April Type II No distinct dry season but Eastern parts of the have a pronounced wet Philippines, coastal areas season from December to facing the Pacific Ocean February Type III More evenly distributed Western Visayas and rainfall throughout the year, MIndanao with no very pronounced wet or dry season Type IV Even distribution of rainfall Most parts of Mindanao throughout the year Figure 2. The climate map of the Philippines based on the modified coronas classification. Source: Alejo, Lanie & Ella, Victor & Lampayan, Rubenito & Delos Reyes Jr, Aurelio. (2021). Assessing the impacts of climate change on irrigation diversion water requirement in the Philippines. Climatic Change. 165. 10.1007/s10584-021-03080-6. D. CLIMATE VARIABILITY AROUND THE WORLD The world’s climate types are classified based on long-term patterns of temperature and precipitation. One of the most widely used classification systems is the Köppen-Geiger climate classification, which categorizes climates into several types based on these factors. Here’s an overview of the major climate types around the world: Figure 3. New and improved Köppen-Geiger classifications. (a) present-day (1980-2016); (b) future map (2071-2100). Source: Beck, H., Zimmermann, N., McVicar, T. et al. Present and future Köppen-Geiger climate classification maps at 1-km resolution. Sci Data 5, 180214 (2018). https://doi.org/10.1038/sdata.2018.214 1. Tropical Climates (A) Tropical Rainforest (Af): o Characteristics: High temperatures year-round with abundant rainfall. There is no significant dry season. o Examples: Amazon Basin in Brazil, Congo Basin in Africa, and parts of Southeast Asia. Tropical Monsoon (Am): o Characteristics: High temperatures year-round with a pronounced dry season, but the wet season is very wet. o Examples: Parts of India, Bangladesh, and the west coast of Africa. Tropical Savanna (Aw/As): o Characteristics: High temperatures year-round with a distinct wet and dry season. The dry season is longer than in tropical monsoon climates. o Examples: Parts of Brazil, northern Australia, and parts of Africa. 2. Arid Climates (B) Desert (BW): o Characteristics: Very low precipitation with high temperature variations between day and night. Hot deserts have high temperatures, while cold deserts can be quite cold in winter. o Examples: Sahara Desert in Africa, Arabian Desert in the Middle East, and the Atacama Desert in Chile. Semi-Arid (BS): o Characteristics: Slightly more rainfall than deserts, with hot summers and cold winters. These regions have more vegetation compared to deserts. o Examples: Parts of the Great Plains in the USA, the Sahel region in Africa, and parts of Central Asia. 3. Temperate Climates (C) Mediterranean (Cs): o Characteristics: Hot, dry summers and mild, wet winters. This climate type is found on the western coasts of continents. o Examples: Southern California, the Mediterranean Basin, and parts of South Australia. Humid Subtropical (Cfa/Cwa): o Characteristics: Hot, humid summers and mild to cool winters with significant rainfall throughout the year. o Examples: The southeastern United States, parts of China, and northeastern Argentina. Oceanic (Cfb/Cfc): o Characteristics: Mild temperatures year-round with no extreme temperature variations and consistent rainfall. o Examples: Western Europe (e.g., the UK, France), parts of New Zealand, and the coastal regions of the Pacific Northwest in the USA. 4. Continental Climates (D) Humid Continental (Dfa/Dfb): o Characteristics: Warm to hot summers and cold winters with significant temperature variations between seasons. Rainfall is fairly evenly distributed throughout the year. o Examples: The northeastern United States, parts of Canada, and eastern Europe. Subarctic (Dfc/Dfd): o Characteristics: Short, warm summers and long, extremely cold winters with low to moderate precipitation. o Examples: Parts of Siberia, northern Canada, and Scandinavia. 5. Polar Climates (E) Tundra (ET): o Characteristics: Very cold temperatures with a short, mild summer. Precipitation is low, mostly falling as snow. o Examples: Parts of Alaska, northern Canada, and coastal areas of Greenland. Ice Cap (EF): o Characteristics: Extremely cold temperatures year-round with no significant seasonal variation. Precipitation is very low, mostly as snow. o Examples: Antarctica and Greenland’s interior. 6. Highland Climates (H) Highland: o Characteristics: Climate varies widely with altitude. Typically, it becomes cooler and wetter with increasing elevation. o Examples: The Andes in South America, the Himalayas in Asia, and the Rockies in North America. E. CLIMATE VARIABILITY AND CLIMATE CHANGE The effects of climate change on climate variability are complex and multifaceted, impacting both the frequency and intensity of various climate events. Here are some ways in which climate change is influencing climate variability: 1. Increased Frequency and Intensity of Extreme Weather Events Heatwaves: Climate change has led to more frequent and intense heatwaves. Higher average global temperatures increase the likelihood of extreme heat events. Droughts and Floods: Climate change can lead to changes in precipitation patterns, resulting in more severe and prolonged droughts in some regions, while others may experience increased rainfall and flooding. Storms and Hurricanes: There is evidence that climate change is making storms, including hurricanes and typhoons, more intense, with higher wind speeds and more precipitation. Warmer sea surface temperatures provide more energy for these storms. 2. Alteration of Seasonal Patterns Shifts in Seasons: Climate change is causing shifts in the timing and duration of seasons. For instance, spring may arrive earlier, and winters may be milder and shorter in many regions. Changes in Monsoon Patterns: In regions dependent on monsoons, such as South Asia, climate change is leading to shifts in the timing, duration, and intensity of monsoon rains, which can have profound impacts on agriculture and water resources. 3. Amplification of Natural Climate Variability El Niño and La Niña Events: Climate change is affecting the frequency and intensity of El Niño and La Niña events, which are natural drivers of global climate variability. There is ongoing research on how these events might be altered in a warmer world, with some studies suggesting more extreme phases of these cycles. Arctic Amplification: The Arctic is warming faster than the global average, which can lead to changes in atmospheric circulation patterns. This can influence weather patterns at lower latitudes, potentially leading to more persistent and extreme weather events. 4. Impact on the Hydrological Cycle Changes in Precipitation Patterns: Climate change is altering the global hydrological cycle, leading to changes in where, when, and how much precipitation occurs. This can result in increased variability in water availability, affecting agriculture, water supply, and ecosystems. Glacial and Snowmelt: Accelerated melting of glaciers and snowpacks due to rising temperatures is affecting water resources in regions that depend on them, leading to variability in river flows and water availability throughout the year. 5. Oceanic Changes Ocean Circulation: Climate change is affecting ocean currents, which play a critical role in regulating climate by distributing heat around the planet. Changes in these currents can lead to shifts in climate patterns, such as altered precipitation or temperature distributions. Sea Level Rise: Rising sea levels, driven by the thermal expansion of seawater and melting ice, can exacerbate the impact of storm surges and coastal flooding, leading to more frequent and severe events. 6. Ecosystem Responses Biodiversity and Ecosystem Shifts: As climate variability increases, ecosystems may struggle to adapt, leading to shifts in species distributions, changes in migration patterns, and disruptions in food chains. Agriculture and Food Security: Increased climate variability can make agricultural planning more difficult, leading to potential crop failures, food shortages, and increased vulnerability of food systems. F. CAUSES OF CLIMATE CHANGE Climate change is driven by both natural processes and human activities, each contributing in distinct ways. Here’s an overview of the natural and human-induced effects of climate change: 1. Natural Effects of Climate Change Volcanic Activity: o Short-term Cooling: Volcanic eruptions can inject large quantities of ash and sulfur dioxide into the stratosphere. These particles reflect sunlight away from Earth, causing temporary cooling. For example, the eruption of Mount Pinatubo in 1991 caused a global temperature decrease of about 0.5°C for several years. Solar Variability: o Changes in Solar Radiation: The Sun’s energy output varies over time due to solar cycles, which can influence Earth’s climate. However, these variations are relatively small compared to the influence of greenhouse gases and are not the primary driver of recent climate change. Natural Greenhouse Gas Emissions: o Methane from Wetlands: Wetlands naturally emit methane, a potent greenhouse gas, into the atmosphere. While this is a natural process, human activities like agriculture and land use changes can exacerbate these emissions. o Carbon Dioxide from Ocean Outgassing: Oceans can release stored carbon dioxide during periods of warming, which further influences the global climate. Ocean Circulation Changes: o El Niño and La Niña: These natural phenomena are part of the El Niño- Southern Oscillation (ENSO) cycle, which causes significant fluctuations in global climate patterns, including temperature and precipitation changes. El Niño generally leads to warmer global temperatures, while La Niña has a cooling effect. Natural Climate Variability: o Ice Age Cycles: Earth’s climate has naturally fluctuated between warm and cold periods over geological timescales, primarily due to changes in Earth’s orbit, axial tilt, and the distribution of continents. 2. Human-Induced Effects of Climate Change Greenhouse Gas Emissions: o Burning of Fossil Fuels: The combustion of coal, oil, and natural gas for energy and transportation is the largest source of human-induced carbon dioxide (CO2) emissions, which is the main driver of current global warming. o Deforestation: Clearing forests for agriculture, urbanization, and other purposes reduces the number of trees that can absorb CO2 from the atmosphere, contributing to higher concentrations of greenhouse gases. o Agriculture: Agricultural activities, including livestock farming, produce significant amounts of methane (CH4) and nitrous oxide (N2O), both potent greenhouse gases. The use of synthetic fertilizers also contributes to nitrous oxide emissions. Land Use Changes: o Urbanization: Expanding cities and infrastructure lead to changes in land surface properties, such as albedo (reflectivity) and heat absorption, which can influence local and regional climates. o Soil Degradation: Intensive farming practices, deforestation, and other land use changes lead to soil degradation and reduced carbon sequestration capacity of soils, further contributing to atmospheric CO2 levels. Aerosol Emissions: o Industrial Pollutants: Human activities, particularly the burning of fossil fuels, release aerosols (tiny particles) into the atmosphere. Some aerosols, like sulfate aerosols, can cool the climate by reflecting sunlight, while others, like black carbon, can contribute to warming by absorbing sunlight. Industrial and Chemical Processes: o Ozone Depleting Substances (ODS): Chemicals such as chlorofluorocarbons (CFCs), used in refrigeration and other industrial processes, have contributed to the depletion of the ozone layer and have also acted as greenhouse gases. o Cement Production: The production of cement is a significant source of CO2 emissions, as it involves the calcination of limestone, which releases CO2 as a byproduct. Alteration of Natural Carbon Sinks: o Ocean Acidification: Increased CO2 levels lead to more CO2 being absorbed by oceans, causing acidification. This impacts marine life and the ocean’s ability to sequester carbon, weakening a vital natural carbon sink. o Forest Degradation: Human activities, including logging and land conversion, lead to forest degradation, reducing the ability of forests to act as carbon sinks. Natural processes have always influenced Earth's climate, but the current trend of rapid warming is largely driven by human activities, particularly the emission of greenhouse gases. While natural factors continue to play a role, the dominant force behind the observed changes in climate over the past century is human-induced, leading to unprecedented impacts on global ecosystems, weather patterns, and sea levels. Online References and Further Reading: https://climatehealthconnect.org/wp-content/uploads/2016/09/Climate101.pdf https://www.pagasa.dost.gov.ph/information/climate-philippines https://www.pagasa.dost.gov.ph/information/climate-change-in-the-philippines https://www.ipcc.ch/report/ar3/wg1/ https://climateknowledgeportal.worldbank.org/country/philippines/climate-data-historical https://koeppen-geiger.vu-wien.ac.at/present.htm https://education.nationalgeographic.org/resource/koppen-climate-classification-system/ https://terra.nasa.gov/science/climate-variability-and-change https://science.nasa.gov/climate-change/effects/ https://niccdies.climate.gov.ph/climate-change-impacts https://www.ipcc.ch/report/ar6/wg1/chapter/chapter-3/ https://science.nasa.gov/climate-change/causes/