ATM S 111, Global Warming: Understanding the Forecast DARGAN M. W. FRIERSON DEPARTMENT OF ATMOSPHERIC SCIENCES DAY 1: OCTOBER 1, 2015 About Me Professor: Dargan Frierson Home town: Wilmington, NC Southeastern North Carolina, on the coast About Me Home town: Wilmington, NC Wilmington, NC Hurricane Fran, 1996 About Me Home town: Wilmington, NC Wilmington, NC Hurricane Floyd, 1999 About Me Home town: Wilmington, NC Wilmington, NC Hurricane Bertha, 1996 About Me Home town: Wilmington, NC Wilmington, NC Hurricane Bonnie, 1998 About Me Home town: Wilmington, NC Wilmington, NC Hurricane Diana, 1984 About Me Undergraduate: North Carolina State, Raleigh, NC Raleigh, NC Total precipitation from Hurricane Fran, 1996 (my freshman year) After Grad School Grad school at Princeton (applied math) Postdoc (2 yrs) at University of Chicago Professor at UW starting 2007 At UW Research primarily on large-scale atmospheric responses to global warming I love teaching! Especially at the undergraduate and introductory level I’ve taught Climate Dynamics, Fundamentals of Climate Change, Modeling the Atmosphere, Atmospheric Motions, Geophysical Fluid Dynamics, Atmospheric Waves and Instabilities, etc Active in creating YouTube videos about atmospheric science with our outreach group Teaching Assistants Two TAs in this class Lexie Goldberger Studies how fire emissions impact atmospheric chemistry Isabel McCoy Studies how low clouds impact the radiative budget of the earth Goals of the Class We’re going to learn about: The science behind global warming How to critically evaluate what you hear about climate and global warming Related issues such as energy alternatives and international agreements on climate Class Outline Weeks 1-2: Overview and global warming science Weeks 3-5: Principles of climate and impacts of climate change Week 6: Climate records, long ago and recent past Week 7: Climate modeling and future projections Week 8: The debate & solutions Week 9: Technological solutions Week 10: Political solutions Required Textbook The Thinking Person’s Guide to Climate Change by Bob Henson Me and Bob Henson at NCAR Required Course Materials “Clickers” for in-class questions and activities Turning Technologies ResponseCard RF AwemoreUW has clickers for rent for $8 per quarter We’ll start clicker questions on Tuesday, so have a clicker by then! Grading Comprehensive final: 25% Quizzes (2): 30% Homework: 25% In-class activities: 20% “Quiz” Sections Actually for discussion, review, and problem solving In class activities for points Go to your registered section only (there’s only room for 30 students in some classrooms) Bring your laptop this week if you have one! Course Webpage http://www.atmos.washington.edu/~dargan/111.html Check it often! It’ll have all reading assignments, links to the HW, slides from lectures, etc Homework Online using canvas (link will be posted on the class website once the first assignment is ready) Also slides from quiz sections are on canvas You’ll get a walkthrough of canvas during sections this week OK to discuss problems with classmates, but turn in your own answers Clicker Questions One point for each right answer or survey question Half a point for wrong answers Grading will be in two week blocks: I’ll set a goal every two weeks for the number of points you need for full credit Get the target score to get full credit Use only your own clicker Other Ground Rules Respect! This can be a politically charged topic: respect your neighbor’s views No talking, texting, e-mail, etc We’ll take a 10 minute break each class period Twitter @DarganF I’ll occasionally tweet links to materials presented in class, places to go for more info about the lectures, relevant news articles, my thoughts about the topics covered, etc Useful for you? Maybe, maybe not… First… A basic summary of the science of global warming Reading assignment for the summary: Henson pp. 3-26, “Climate Change: A Primer” FAQ about climate change Also for next class: Henson pp. 27-40, “The Greenhouse Effect” The Atmosphere From Space Weather versus Climate Weather varies from one day to the next Climate: averages of the weather over a longer period of time Example: You put on clothes for the weather… Should I pack an umbrella? You buy clothes for the climate… Going where the climate suits my clothes – lyrics from Lonesome Road Blues (traditional, e.g., Henry Whitter, 1924) Both weather and climate can be predicted with some fidelity Weather vs. Climate Weather is like your mood… Climate is like your personality… Weather vs Climate in Western N. America Weather is the individual storms Climate is the fact that all of them hit western WA! Animation of cloud thickness from a climate model What Factors Influence Climate? Sunshine And relatedly, latitude Topography/mountains Proximity to oceans and large lakes Ocean currents Presence of trees/vegetation Etc. The atmosphere from space… 90% of the mass of the atmosphere is within 16 km (10 miles) of the surface Proportionally, the atmosphere is half as thin as seams on a basketball It’s remarkably thin… A thin atmosphere means we can change atmospheric composition We Modify the Composition of the Atmosphere Carbon dioxide (CO2) has been measured at Mauna Loa, Hawaii since 1958 “Keeling curve”: first measured by David Keeling in March ’58 Over 25% increase since the first measurement Human induced: Due to fossil fuel burning (90%) and deforestation (10%) Let’s Look Way Back to 450,000 Years We’re at 400 ppm now Natural variation over Ice Age Cycles: 180-280 ppm 280 Current rate of increase is 100-1000 times faster than nature can change CO2 180 Past Present Img src: Global Warming Art CO2 is a Greenhouse Gas Greenhouse gases slow heat loss to space Has been known for a long time (J. Fourier in 1824) This is why it’s hot The Sun heats the Earth. Greenhouse gases cause the Earth to be a lot warmer than if there was no atmosphere: 58o F (32o C) warmer The natural greenhouse effect Joseph Fourier The Earth is Warming More CO2 -> warmer atmosphere (eventually) Has it been getting warmer? It’s warmed about 0.8o C (1.5o F) in the last 130 years 1o F 0.5o F Especially rapid warming since the mid-’70s 13 out of the top F 14 hottest years on record were the o -0.5 F last 13 years 0o Src: NASA GISS Warming has happened almost everywhere. Northern high latitudes have warmed the most. Land has warmed more than ocean. Source: IPCC AR5 Isn’t there controversy about this data? No, we’re confident about the thermometer data There has been discussion about tree ring reconstructions (known as the “hockey stick”): 1o F This is less certain, and only represents the Northern Hemisphere 0o F anyway (gray area indicates uncertainty) -1o F We’ll discuss this and other controversies more later… -2o F Src: IPCC AR3 What Else is Happening? Arctic sea ice is melting The ocean is gaining heat Sea level is rising 20 cm = 8 inches Also glaciers are melting, humidity is increasing, species are shifting, etc Src: IPCC AR5 Glacier retreat We don’t have to go far to see the retreat of mountain glaciers… 1973 White Chuck glaci North Cascades 2006 What’s Predicted for the Future? A fundamental uncertainty is future human behavior Will we reduce emissions, or will we burn fossil fuels more and more rapidly? How quickly will developing countries get rich, and will they use the same dirty fuels as we have? Future Temperature Rise Predictions Uncertainty both in human behavior (colors) and climate feedbacks (shaded area around) Climate models are saying “you ain’t seen nothin yet” 6o F 4o F 2o F 0o F Src: IPCC AR5 Business as usual would mean 3-5.5o C (5.5-10o F) more warming “Utopia”: 0.5-1.5o C (0.9-2.7o F) increase Controversy About All This? No doubt about these things: The greenhouse effect That CO2 and other greenhouse gases are increasing due to man That temperatures are rising Skeptics tend to argue for: “Negative feedbacks” that keep the temperature changes small Or that warming wouldn’t be such a bad thing Or about flaws in a particular study Be wary: Much of “the debate” (on both sides) is not very scientific Let’s sort out fact from fiction! A Sampling of Future Topics “Paleoclimate”: Ice Ages and hot climates of the past like the Cretaceous Ice sheet extent Last Glacial Maximum Present The Cretaceous Seaway Volcanoes and Climate How the Earth cools after certain types of volcanoes… Eruption of Mount Pinatubo in June 1991 and its effect on global temperatures And Man-Made Volcanoes! “Geoengineering”: using technology to cool the Earth People are considering things like Putting volcanic-type particles into the stratosphere Space mirrors Cloud machines Fake trees Right picture from Rolling Stone article “Can Dr. Evil Save the World?” The Effect of Climate on Nature Cute animal pictures!! Climate and the Rainforests The effect of burning tropical rainforests on climate And the effect of climate change on rainforests Rainforests burning over the Brazil-Bolivia border Satellite photo from NASA (MODIS): Locations of fires marked by (enhanced) red dots Winners and Losers Who will benefit… New shipping lanes • And who will it hurt the most? Floods Floods in Yemen, October 2008 And Droughts… Lake Chad UNEP Alternative Energies & Fuels Pros and cons of wind, solar, nuclear, ethanol, etc Science and Policy The ozone problem This was solved by the most efficient interaction between science and policy to date Discovery of the ozone hole led to a ban on all CFCs Why is global warming so much more difficult from a policy perspective? Very Exciting Time for Climate Science! One of the strongest El Niño events in history is occurring Hottest year in human history Paris meeting: Nov-Dec 2015 Many are optimistic about the world making big progress on reducing emissions Let’s Get Started! First topic: the science of global climate What are the key factors that determine the temperature of Earth?