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Understanding Ocean and Earth System Science through models l l l Understanding the contemporary Earth System Science relies on the recruitment and formation of a generation of young scientists with the capabilities to analyze the products of climate and Earth System Models. Capacity building in human and technological resources should be an integral component of the curriculum. This should go beyond the traditional boundaries of the scientific disciplines taught at universities. We target undergraduate and early graduate students from Science, Engineering and Economics faculties in South Africa, which provide introductory courses in Information Technology, Computing, Applied Mathematics, Physics, Chemistry and Earth Sciences. AGENDA Lectures 10h30-11h30 Enrico Scoccimarro ESM crash course part 1: the physical components 11h30-12h30 Marcello Vichi ESM crash course part 2: the carbon cycle 12h30-13h30 B reak Hands-on session 13h30-15h00 Group A 15h00-16h30 Group B E S M crash cour se part 1: the physical components E nrico S coccimarro Istituto Nazionale di Geofisica e Vulcanologia - INGV Centro euro-Mediter raneo sui Cambiamenti Climatici - CMCC B ologna, Italy enrico.scoccimarro@ ingv.it The euro Mediterranean Center on Climate Change (CMCC) mission is to investigate and model our climate system and its interactions with society to provide reliable, rigorous, and timely scientific results to stimulate sustainable growth, protect the environment, and to develop science driven adaptation and mitigation policies in a changing climate. h" p://www.cmcc.it [email protected] Outline • Physics of climate: a brief introduction • Anthropogenic impacts on the past climate • Climate Models, future scenarios and projections ESM crash course part 2: the carbon cycle Outline • Physics of climate: a brief introduction • Anthropogenic impacts on the past climate • Climate Models, future scenarios and projections ESM crash course part 2: the carbon cycle Let’s start talking about Heat !!!!!! • Heat transfers in three ways: • ConducAon • RadiaAon • ConvecAon <- Responsible of the heat transfer from the Sun to the Earth Planet <- Dominates the heat transfer over the Earth Planet The radiation method of heat transfer How does heat energy get from the Sun to the Earth? ? There are no particles between the Sun and the Earth so it CANNOT travel by conduction or by convection. RADIATION The Climate Machine Solar Radiation H2O CH4 CO2 Earth Radiation N2 O2 The energy that drives the climate system comes from the Sun Greenhouse gasses are mainly stored in the Troposphere Earth Radius ? 6000 km! Energy radiates from the earth surface Radia4on from the sun warms the earth’s surface Energy radiates from the atmosphere Greenhouse gases are being warmed by the radia4on from earth Without With greenhouse gases: +15 -18 degrees! Solar radiaAon 1360 W/m2 (Solar Constant) 63 x 106 W/m2 As the Sun's energy spreads through space its spectral characteristics do not change because space contains almost no interfering matter. However the energy flux drops monotonically as the square of the distance from the Sun. Thus, when the radiation reaches the outer limit of the Earth's atmosphere, several hundred kilometers over the Earth's surface, the radiative flux is approximately 1360 W/m2 SST - Sea Surface Temperature [oC] The Earth is a sphere and aside from the part closest to the sun, where the rays of sunlight are perpendicular to the ground, its surface tilts with respect to the incoming rays of energy with the regions furthest away aligned in parallel to the radiation and thus receiving no energy at all CONVECTION ConvecAon red= hot blue = cold The Atmospheric CirculaAon The Ocean CirculaAon The Ocean CirculaAon (OGCM results) [latitude] The climatological meridional heat transport [PW] Types of CLIMATE Outline • Physics of climate: a brief introduction • Anthropogenic impacts on the past climate • Climate Models, future scenarios and projections ESM crash course part 2: the carbon cycle Changes in atmospheric CO2 concentration Keeling curve named after Charles “Dave” Keeling http://www.esrl.noaa.gov/gmd/ccgg/iadv/ Why “unprecedented perturbation”? Climate Variability and Change – Fall School on "Modeling CC Impacts on Water and Crops at Different Scales”, November 5 2012 - Alghero Why “unprecedented perturbaAon”? Falkowski et al. (2000) Surface Temperature evolution in the past years Temperature change difference (2001-2015) - (1850-1899): +0,79 ± 0,19 ! C Climate Variability and Change – Fall School on "Modeling CC Impacts on Water and Crops at Different Scales”, November 5 2012 - Alghero Past changes in Arctic Sea Ice extension Past changes in the annual cycle of sea ice extent Arctic Sea Ice Volume: time evolution since 1979 Past changes in Glaciers extension 1893 2008 Vallelunga glacier Alpine glaciers mass evolution since 1945 Past evolution of the Sea Level High Outline • Physics of climate: a brief introduction • Anthropogenic impacts on the past climate • Climate Models, future scenarios and projections ESM crash course part 2: the carbon cycle SCIENTIFIC METHOD AND CLIMATE SCIENCE •The Oxford English Dictionary says that scientific method is: "a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.” •This definition whould require the possibility to test our hypothesis as many times as possible to be sure of its statistical significance. •In the context of climate “empirical science” is not applicable because it would require a spare earth to experiment on. And even if this spare earth existed it would take many years, at least 30 but in some cases, thousands or millions of years to test our hypotheses on it. 33 Laboratory experiments? •This is an important consideration, because it is precisely such wholeEarth, system-scale experiments, incorporating the full complexity of interacting processes and feedbacks, that might ideally be required to fully verify or falsify climate change hypotheses (Schellnhuber et al., 2004, in Chap. 1, IPCC WG1, 2007). •That’s where numerical climate models come for help. Global models: a brief history In 1904, Norwegian scientist Vilhelm Bjerknes first argued that it should be possible to forecast weather from calculations based upon natural laws. “Based upon the observations that have been made. The initial state of the atmosphere is represented by a number of charts which give the distribution of 7 variables …With these chatrs …new charts ..are to be drawn wich represent the new state of the atmosphere from hour to hour.” However no analytic methods for solving the physical equations involved were known at that time, so Bjerknes was forced to rely on graphical methods. 35 Lewis Fry Richardson •In 1922, Lewis Fry Richardson devised an algorithmic scheme for weather prediction based on solving partial differential equations. •He set out to formulate a set of equations tha would completely determine the behaviour of the atmosphere given its initial state. This set later on became the well known primitive equations: 2 1 3 4 36 Lewis Fry Richardson •Richardson proposed a computational strategy for the entire globe, introducing the primal concept of discretization through the finite differences method. •For a forecast of 6-hour Richardson needed 6 weeks of intense labour and finally ended up with a completely wrong solution!!! •“Perhaps some day in the future it will be possible to advance the computations faster than the weather advances and at a cost less than the saving to mankind due to the information gained. But that is a dream” 37 The model grid 38 the problem of the resolution Resolution 1 Resolution 2 39 I The Hansen et al. model ( 1983) •8° latitude by 10° longitude, 9 vertical levels up to 10 mb. Topography and vegetation. •The physical processes of momentum and energy transfer among atmosphere, ocean (sea ice) and land are solved at each grid point. •The model also inc1udes the radiative influence of CO2 , H20 and other gases · ·.: ..·: .':·..":.....· .. -- - - - -, - --C-l ·-y-J--COit - C h 'ie d , rod 1iott J : __ _ ____ , _ __ en i 11fflh L -- H,.O,C01, 0 , , lmr gnsts, (Jo -1, C . .... ......,... "'-'·" .. , .. :IIJ r :t : n . t b":, '* ·' IC- ... - - • - - 1 - - - ... .. Numerical climate models •Investigation tools •Prognostic models of the general circulation of the ocean and atmosphere •Based on physical equations of mass and energy balance •Discretized numerical solutions at given spatial gridpoints General Circulation Model (global scale) resolution: a zoom over EU orography 2001 1990 2007 1996 42 General Circulation Model (global scale) orography resolution: a zoom over EU 2007 AR5 2013 now HighResMIP within CMIP6 (6th phase of the Coupled Model Intercomparison Project that will provide climate 43 data for the next Intergovernmental Panel on Climate Change - IPCC Assessment Report) General Circulation Model (global scale) orography resolution: a zoom over the South Pacific basin Scale of phenomena 45 Development: From Atmosphere only General CirculaAon Models (GCMs) through fully Coupled Atmosphere – Ocean models (CGCMs) to Earth System Models (ESMs) AR5 Last IPCC Assessment Reports (AR4 and AR5) leverage on Couple Model Intercomparison Projects (CMIP3 and CMIP5) Horizontal resolution between CMIP3 (AR4) and CMIP5 (AR5) didn’t change significantly COUPLED MODEL HIERARCHY No dynamics SWAMP OCEAN (no heat storage) Downward infraRed Sensible HF S + Fd – Fu – H - Latent LE =HF0 Absorbed solar Upward infraRed SLAB/MIXED LAYER OCEAN OCEAN GCM Trenberth, 1992 I The phys·ca ·nterface Sea le igure 2 ch sea i ·c mod o th h ng tw en s (includin , c· bon rela oo ii ld ·). 1 I a er d th o n- FIELD EXCHANGE BETWEEN ATMOSPHERE AND OCEAN MODELS The interpolation issue. ORCA2 grid ECHAM -T106 grid Atmosphere/Ocean-Sea Ice coupled model FIELD EXCHANGE BETWEEN ATMOSPHERE AND OCEAN MODELS The interpolation issue. Atmosphere/Ocean-Sea Ice coupled model Northern Hemisphere Grids ECHAM-T30 ORCA2 ECHAM-T106 ORCA2 An example of a CMIP5 Climate model: CMCC-CM Atmosphere/Ocean-Sea Ice coupled model Atmosphere ECHAM 5 (70 km horiz. res.) Coupler OASIS 3 (Ocean Atmosphere Sea Ice Soil ) Ocean Sea-Ice ORCA2 OPA 8.2 (50-200 km horiz. res.) LIM (Louvain-La-Neuve sea-Ice Model ) Earth System experiments • Climate Models are mainly used for •process studies: to be" er understand the relaAonship within the climate system •aSribu4on studies: understanding the causality between observed changes and the major natural and anthropogenic forcings •scenario studies: making future projecAons on the state of the climate according to predefined scenarios of anthropogenic usage of the Earth resources ProjecAons •Climate scientists never use the term prediction when referring to future climate conditions. •This stems from the fact that a future climate simulation is not exactly an “initial value problem” but mostly a “boundary value problem” •The correct term is “projection”, because the models are used to project into the future the climate conditions driven by a set of predefined, time-evolving forcing scenarios. Future scenarios: where do they come from? •A SCENARIO is a plausible description of how the future may develop, based on a coherent and internally consistent set of assumptions about key relationships and driving forces (e.g., population, rate of technology change, prices). Note that scenarios are neither predictions nor forecasts. (OECD, Organisation for Economic Co-operation and Development ) http://www.ipcc.ch/ipccreports/sres Emission scenarios: SRES in AR4 and RCPs in AR5 m o l e fraction of C H 4 in air 4000 RCP4.5 RCP8.5 A1B HIST 3500 [CH4] METHANE [ ppbv ] 3000 2500 2000 1500 1000 1950 1960 1970 1980 1990 2000 2010 2020 2030 year 2040 2050 2060 2070 2080 2090 2100 m o l e fraction of C O 2 in air 1000 900 RCP4.5 RCP8.5 A1B HIST 800 [ ppmv ] CARBON DIOXIDE [CO2] 700 600 500 400 300 1950 1960 1970 1980 1990 2000 2010 2020 2030 year 2040 2050 2060 2070 2080 2090 2100 Future emission scenarios: SRES in AR4 e RCPs in AR5 m o l e fraction of C O 2 in air 1000 RCP4.5 RCP8.5 A1B HIST 900 CO2 800 [ ppmv ] 700 600 500 400 300 1950 1960 1970 1980 1990 2000 2010 2020 2030 ye a r 2040 2050 2060 2070 2080 2090 2100 for the first 4me (AR5) Representa4ve Concentra4on Pathways (RCPs) will include scenarios that explore approaches to climate change mi4ga4on in addi4on to the tradi4onal „no climate policy‟ scenarios INGV-CMCC CMIP5 IPCC Experiments: the historical run XX sec. Ozone XX sec. Sulfate aerosols 2d, zonal mean, monthly fields 3d, monthly fields monthly freq. CMCC-CM Historical yearly freq. XX sec. N2O Global value, yearly XX sec. CH4 Global value, yearly XX sec. CFCs XX sec. CO2 Global value, yearly Global value, yearly IPCC AR5 global projections Climate Model Data The Coupled Model Intercomparison Project – CMIP as climate data provider to the Intergovernmental Panel on Climate Change IPCC Reports http://cmip-pcmdi.llnl.gov/cmip5/availability.html IPCC AR5 global projections CO2 2 meter Temperature anomaly wrt 1961-1990 Mean sea level anomaly wrt 1961-1990 Observations since 1950 compared with projections from the previous IPCC assessments. Observed globally and annually averaged CO2 concentrations in parts per million (in ppm) Estimated changes in the observed globally and annually averaged surface temperature anomaly relative to 1961–1990 (in °C) Estimated changes in the observed global annual mean sea level (in cm) w World Climate Research Programme • About .., Core Projects Co-sponsored activities ... WMO Sitemap mm• Unifying Themes .., IOC Grand Challenges .., Key Deliverables .., Resources .., CMIP Phase 6 (CMI P6) Overview CMIP6 Experimental Design and Organization e W GCM 0 About WGCM 0 Members CM IP The overview paper o n the CMIP6 experimental desig n and organization has now been publ shedin GMO (Eyrin g et al., 20 16) . This C M IPS overview paper presents the b ackground and rationa le for the new structure of CM IP, prov des a detaile d descrip t io n of the CMIP Diag nostic, Evaluation and C haracterization of Klim a (DECK) 0 About CMIP experiments and CMIP 6 historical s im ulations, andin c lu des a b riefin troduction to the 21 CMIPS-Endorsed MIP s. 0 CMIP3 A brief summary can be fou n d in the following overview presentation (CMIP6Fina1Desig n_GMD_ 160603.pdf) and (> CMIPS below. After a long and wide community oonsultation, a new and more federated structure has been pu tin p lace.It 0 consists of ttYee major elements: 1. a handful of common experiments, the DECK (Diagnostic, Evaluation a nd Characterizat ion of Klima) and CMIP CMIP 6 (> Catalogue MIP s historical s imu la tions (185 0 - n e ar-present) that will m ain tain continuity and help docume nt basic characteristics (> CMIPS-Endorsed P I s M of models across dif ferent phases of CMIP, 2. common standards , coordination, infrastructure and docum entation that will fac i tate the d istributio n of model (> Other a c t ive MIPs outputs and the characterizatio n of the model e nsemble , and > 3 . a n e nsemble of CMIP- Endorsed M o del lntercomparison Projects (MIP s} that will be specific to a particular phase of CMIP (now CMIPS) a nd that will b uild o n the DECK and CMIP h istorical s im u la tions to address a la rge range of specific q uestions and fill the scientific gaps of the previous CMIP phases. 0 Fo rmer MIPa Decadal predlctJon (> MeetJng s EARCHINSTITUTE ·---·-C-LAMP ARM ESGF m• • • - -_--_-_ CSSEF DOEJANL obs4MIPs MERRA l ESG NASA/JPL NASA/NCCS t Ear t h System Grid Federation GMAO IPSL I j NOAA/ESRL . . - ANU/NCI I . ·- -- . -..-·----- ·-··-- ·- --.. - -' ·- . -. -- -- MARINERESEARCHINSTITUTE https ://pcmdi.llnl.gov Golden r ules for us ing climate model data 1. Models are “models ”, not reality. Carefully cons ider the underlying ass umptions 2. Climate models resolve climatic features. T here is no year 1998, but the climate of the 90’s . 3. Climate s cience is based on s everal realizations becaus e climate is intrins ically variable: do not cherr y-pick one model unless for s pecific pur pos es 4. Cons ider the s patial resolution (gr id s ize) and temporal frequency 5. Us e like with like. Carefully read the definition of the model variables Outline • Physics of the climate: a brief introduction Due to induced - additional computational costs, Earth System Models (ESM) run with a lower horizontal resolution compared to Coupled General Circulation Models (CGCM), • Anthropogenic impacts on the past climate but the possibility to realistically represent the Carbon Cycle within the Climate System, gives the possibility to better Investigate climate changesand under different • Climate Models, future scenarios projections future emission scenarios ESM crash course part 2: the carbon cycle QUESTIONS !!!!! Picture by Paola Secco [email protected] IPCC 4th Assessment Report (AR4, 2007) ▪Global atmospheric concentraAons of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human acAviAes since 1750 and now far exceed pre-industrial values determined from ice cores spanning many thousands of years. The global increases in carbon dioxide concentraAon are due primarily to fossil fuel use and land use change, while those of methane and nitrous oxide are primarily due to agriculture (WG1 SPM) § Warming of the climate system is unequivocal, as is now evident from observa5ons of increases in global average air and ocean temperatures, widespread mel5ng of snow and ice, and rising global average sea level (WG1 SPM) § From new es5mates of the combined anthropogenic forcing due to greenhouse gases, aerosols and land surface changes, it is extremely likely that human ac5vi5es have exerted a substan5al net warming influence on climate since 1750. (WG1-TS6.1) IPCC 5th Assessment Report (AR5, 2013) 1/5 ▪Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentraAons of greenhouse gases have increased. § Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850. In the Northern Hemisphere, 1983–2012 was likely the warmest 30-year period of the last 1400 years. § Ocean warming dominates the increase in energy stored in the climate system, accounAng for more than 90% of the energy accumulated between 1971 and 2010 (high confidence). It is virtually certain that the upper ocean (0−700 m) warmed from 1971 to 2010, and it likely warmed between the 1870s and 1971. IPCC 5th Assessment Report (AR5, 2013) 2/5 ▪Over the last two decades, the Greenland and AntarcAc ice sheets have been losing mass, glaciers have conAnued to shrink almost worldwide, and ArcAc sea ice and Northern Hemisphere spring snow cover have conAnued to decrease in extent (high confidence). § The rate of sea level rise since the mid-19th century has been larger than the mean rate during the previous two millennia (high confidence). Over the period 1901–2010, global mean sea level rose by 0.19 [0.17 to 0.21] m. § The atmospheric concentraAons of carbon dioxide (CO2), methane, and nitrous oxide have increased to levels unprecedented in at least the last 800,000 years. CO2 concentraAons have increased by 40% since pre-industrial Ames, primarily from fossil fuel emissions and secondarily from net land use change emissions. The ocean has absorbed about 30% of the emi" ed anthropogenic carbon dioxide, causing ocean acidificaAon. IPCC 5th Assessment Report (AR5, 2013) 3/5 § Human influence on the climate system is clear. This is evident from the increasing greenhouse gas concentraAons in the atmosphere, posiAve radiaAve forcing, observed warming, and understanding of the climate system. § Climate models have improved since the AR4. Models reproduce observed conAnental-scale surface temperature pa " erns and trends over many decades, including the more rapid warming since the mid-20th century and the cooling immediately following large volcanic erupAons (very high confidence). § ObservaAonal and model studies of temperature change, climate feedbacks and changes in the Earth’s energy budget together provide confidence in the magnitude of global warming in response to past and future forcing. IPCC 5th Assessment Report (AR5, 2013) 4/5 ▪Human influence has been detected in warming of the atmosphere and the ocean This evidence for human influence has grown since AR4. It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. § ConAnued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. LimiAng climate change will require substanAal and sustained reducAons of greenhouse gas emissions. § Global surface temperature change for the end of the 21st century is likely to exceed 1.5°C relaAve to 1850 to 1900 for all RCP scenarios except RCP2.6. It is likely to exceed 2°C for RCP6.0 and RCP8.5, and more likely than not to exceed 2°C for RCP4.5. Warming will conAnue beyond 2100 under all RCP scenarios except RCP2.6. Warming will conAnue to exhibit interannual-todecadal variability and will not be regionally uniform. IPCC 5th Assessment Report (AR5, 2013) 5/5 ▪Changes in the global water cycle in response to the warming over the 21st century will not be uniform. The contrast in precipitaAon between wet and dry regions and between wet and dry seasons will increase, although there may be regional excepAons. § The global ocean will conAnue to warm during the 21st century. Heat will penetrate from the surface to the deep ocean and affect ocean circulaAon. § It is very likely that the ArcAc sea ice cover will conAnue to shrink and thin as global mean surface temperature rises. Global glacier volume will further decrease. § Global mean sea level will conAnue to rise during the 21st century. Under all RCP scenarios the rate of sea level rise will very likely exceed that observed during 1971–2010 due to increased ocean warming and increased loss of mass from glaciers and ice sheets. ▪ Most aspects of climate change will persist for many centuries even if emissions of CO2 are stopped. This represents a substanAal mulA-century climate change commitment created by past, present and future emissions of CO2. The RadiaAve Balance A Phase space view Intergovernmental Panel on Climate Change: the 5th Assessment Report IPCC – AR5 WG II: Impacts, Adaptation, and Vulnerability WG I: The Physical Science Basis WG III: Mitigation of Climate Change Observed Changes in the Climate System Key SPM Messages 19 Headlines on less than 2 Pages Summary for Policymakers ca. 14,000 Words 14 Chapters Atlas of Regional Projections 54,677 Review Comments by 1089 Experts 2010: 259 Authors Selected 2009: WGI Outline Approved Observed Changes in the Climate System WGI - IPCC 5° Assessment Report Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentraAons of greenhouse gases have increased. Ocean warming dominates the increase in energy stored in the climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010 (high confidence). It is virtually certain that the upper ocean (0–700 m) warmed from 1971 to 2010. Over the last two decades, the Greenland and Antarc4c ice sheets have been losing mass, glaciers have conAnued to shrink almost worldwide, and Arc4c sea ice and Northern Hemisphere spring snow cover have conAnued to decrease in extent (high confidence). The rate of sea level rise since the mid-19th century has been larger than the mean rate during the previous two millennia (high confidence). Over the period 1901 to 2010, global mean sea level rose by 0.19 [0.17 to 0.21] m. The atmospheric concentra4ons of carbon dioxide, methane, and nitrous oxide have increased to levels unprecedented in at least the last 800,000 years. Carbon dioxide concentra4ons have increased by 40% since pre-industrial 4mes, primarily from fossil fuel emissions and secondarily from net land use change emissions. The ocean has absorbed about 30% of the emiS ed anthropogenic carbon dioxide, causing ocean acidificaAon. Changes in surface temperature Figure SPM.1a Observed globally averaged combined land and ocean surface temperature anomaly 1850-2012 All Figures © IPCC 2013 Figure SPM.1b Observed change in surface temperature 1901-2012 Changes in Criosphere and Oceans Figure SPM.3 MulAple observed indicators of a changing global climate All Figures © IPCC 2013 Climate change: detecAon and a " ribuAon • Climate change refers to any change (mean state and/ or variability) in climate over time (sufficiently long .. 30years! ), whether due to natural variability or as a result of human activity • Detection of climate change is the process of demonstrating that climate has changed in some defined statistical sense, without providing a reason for that change. • Attribution of causes of climate change is the process of establishing the most likely causes for the detected change with some defined level of confidence (Chapter 1, AR5, IPCC WG1) Extreme Events • “There are a number of ways extreme climate events can be defined, such as extreme daily temperatures, extreme daily rainfall amounts, large areas experiencing unusually warm monthly temperatures, or even storm events such as hurricanes. Extreme events can also be defined by the impact an event has on society. That may involve excessive loss of life, excessive economic or monetary losses or both.” (Easterling et al. 2000) Convection What happens to the particles in a liquid or a gas when you heat them? The particles spread out and become less dense. This effects fluid movement. What is a fluid? A liquid or gas. Fluid movement Cooler, more dense, fluids sink through warmer, less dense fluids. In effect, warmer liquids and gases rise up. Cooler liquids and gases sink.