MEA 593 Climate Risk Analysis for Adaptation Instructor – Fredrick Semazzi

1. MEA 593 Climate Risk Analysis for Adaptation Instructor – Fredrick Semazzi Lecture-2: Review of Prerequisite Fundamentals of Climate Change Science

2. Purpose of Review: To Provide Background Climate Change Science Knowledge for, “MEA 593 Climate Risk Analysis for Adaptation” Approach: For each review topic the class discusses the following question, ‘why is this topic important for the application of climate change information in the development of adaptation and mitigation strategies”.

3. TOPICS• Components of the climate system (atmosphere, hydrosphere, cryosphere, lithosphere, biosphere/humans)• Basic structure of the atmosphere (e.g. troposphere, stratosphere, temperature profile), atmospheric composition, variables used to describe fluid systems and fundamental units (e.g. temperature, density, pressure, zonal vs. meridional wind, etc.)• The Climate System: Controls on Climate• Climate Models• Fundamentals of energy and energy transfer: electromagnetic spectrum, shortwave vs. longwave, conduction, convection, radiation principles (frequency, wavelength, laws), land/ocean fluxes; absorption, emission, scattering, latent vs. sensible energy, greenhouse effect, and albedo• Climate observational networks (surface, upper air, oceanic datasets, satellite data, field projects, reliability of data)• Mean state of the atmosphere – global temperature (seasonal variability), geopotential height, general circulation (wind, pressure, climatological features), variability of the general circulation, precipitation, cloudiness• Mean state of the oceans – temperature (horizontal and vertical), temperature variability, salinity, surface circulation; thermohaline circulation)• Exchange processes between the surface and the atmosphere• Climate variability (natural) – Many time scales, ENSO, NAO, PNA, AMO, PDO, MJO, Milankovitch cycles, volcanic activity, solar variability, paleoclimatology• Global Framework for Climate Services (GFCS)• Climate variability (anthropogenic) – Evidence for, greenhouse gas trends, land use change, pollution and aerosol contributions• Climate Change Projections• Climate Feedbacks

4. Topic Introduction/perspectives, overview of climate (weather vs. climate), components of the climate system (atmosphere, hydrosphere, cryosphere, lithosphere, biosphere/humans) Components of the Climate System • Atmosphere: Layer of gases surrounding the planet Earth that is retained by Earth's gravity; Air, Clouds, Aerosals • Hydrosphere: Combined mass of water found on, under, and over the surface of a planet. • Cryosphere: Portions of the Earth’s surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps and ice sheets, and frozen ground (which includes permafrost). • Lithosphere: Rigid outermost shell of a rocky planet. On Earth, it comprises the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater • Biosphere/humans: Global sum of all ecosystems. It can also be called the zone of life on Earth. 

5. TopicBasic structure of the atmosphere (e.g. troposphere, stratosphere, temperature profile), atmospheric composition, variables used to describe fluid systems and fundamental units (e.g. temperature, density, pressure, joule, watt, zonal vs. meridional wind, etc.)- Origin of the Earth and Atmosphere: Early Atmosphere, timeline for occurrence of gases; processes involved- Present Atmospheric Composition: Gases; percentages- The Carbon Cycle; carbon sources & sinks; human contribution in relatively short time; greenhouse effect; concept of constant and variable gases and what they are; atmospheric structure/layers & explanations for characteristics in different layers;

6. Atmospheric Vertical Structure

7. Topic– The Climate System: Controls on Climate • Six factors cause the climate of a location to have its fundamental characteristics: • Latitude • Earth-Sun Relationships • Distance to Large Bodies of Water (continentality) • Circulation • Topography • Local Features

8. - Description: Climate models are systems of differential equations based on the basic laws of physics, fluid motion, and chemistry. To “run” a model, scientists divide the planet into a 3-dimensional grid, apply the basic equations, and evaluate the results. Atmospheric models calculate winds, heat transfer, radiation, relative humidity, and surface hydrology within each grid and evaluate interactions with neighboring points • - There are both atmospheric GCMs (AGCMs) and oceanic GCMs (OGCMs). • Components of Modern GCMs (Earth System Models) include: ice sheet model; biosphere model; cloud model, hydrodynamics model, land surface model, ocean model, etc • The fluid equations for AGCMs are discretized using either the finite difference method or the spectral method; nested grid climate models Topic:Global Climate Models

9. CLIMATE MODELS COMPONENTS Darker color corresponds to more advanced module

10. Coupling of the Ocean General Circulation Models (OGCMs) & Atmospheric General Circulation Models (AGCMs)Guiding question: Identify the processes through which the evolution of the atmosphere and the ocean are coupled Interfacial fluxes • Longwave radiation flux • Solar radiation flux • Sensible heat flux • Momentum flux (wind stress & C-stress) • Latent heat flux • Salinity flux (function of P-E) P>E imply seawater becomes less saline P<E imply seawater becomes more saline

11. Regional Climate Models (Nested Models) • What they are; How they work; What are their advantages and disadvantages compared to GCMs • RCMs work by increasing the resolution of the GCM in a small, limited area of interest. • RCM might cover an area the size of western Europe, or southern Africa - typically 5000km x 5000km. • The full GCM determines the very large scale effects of changing greenhouse gas concentrations, volcanic eruptions etc. on global climate. • The climate (temperature, wind etc.) calculated by the GCM is used as input at the edges of the RCM. • RCMs can resolve the local impacts given small scale information about orography (land height), land use etc., giving weather and climate information at resolutions as fine as 50 or 25km.

12. Topic Fundamentals of energy and energy transfer: electromagnetic spectrum, shortwave vs. longwave, conduction, convection, radiation principles (frequency, wavelength, laws), land/ocean fluxes; absorption, emission, scattering, latent vs. sensible energy, greenhouse effect, and albedo

13. Basic Definitions/Descriptions • Absorption, • Emission, • Scattering, • Latent vs. sensible energy, • Greenhouse effect, • Albedo

14. Shortwave vs. Longwave See NASA video for visual illustrations: http://www.youtube.com/watch?v=snNwE6txxP0

15. . **Note:The magnitude of the Earth curve has been magnified 500,000 times

16. Black Body Radiation and Properties (frequency, wavelength, laws) Wien’s law: The relationship between maximum power radiated and body temperature

17. Radiation Principles and Properties (frequency, wavelength, laws) The Stefan–Boltzmann law, shows the relationship between absolute temperature and the total energy flux emitted by a black body over the entire wavelength range

18. Planetary Albedo

19. Definitions of the NON-RADIATIVE contributions to atmospheric heat energy - conduction, (QG :substrate heat flux) - convection, (QH :convective or sensible heat flux) - latent heat, (QE :latent heat flux)

20. Net Radiation Balance through any flat surface Energy Balance at the Bottom and Top of the Atmosphere SW LW ATMOSPHERE SW Q*=QH + QE + QG LW SW

21. NASA (http://science.larc.nasa.gov) • 100% incoming SW; 30% reflected back; 70% (absorbed by atm/surface system as SW) balanced by 64%+6%=70% radiated back as LW • 70%(avail)=51% (ab. Land/oce)+3% (ab. clouds) +16% • - 6% = Reflected by atmosphere back to spacexample • breakdown is not on LHS which deals with only SW • 51% (avail from land/oce)=7% (conduction & convection)+23% (LH)+6% (lost to space directly)+15%(ab. Atm-greenhouse effect-number to watch in future climate change scenarios) • 64% (LW lost to spc from cl & atm)= abs[7% (from conduction & convection)+23% (LH)+3% (cl)+16%(atm)+15% (from greenhouse effect)]

22. Topic:Climate observational networks (surface, upper air, oceanic datasets, satellite data, field projects, reliability of data)

23. Topic- Climate observational networks Task Group on Data and Scenario Support for Impacts and Climate Analysis (TGICA) http://www.ipcc.ch/pdf/activity/tgica-mandate.pdf TGICA Activities • TGICA coordinates a Data Distribution Centre (DDC) • TGICA identifies information needs in support of IPCC work • TGICA contributes to building capacity in the use of data Mission of the DDC • Provides access to data sets, climate and other scenarios, and other materials (e.g., technical guidelines on use of scenarios). • DDC operates under the oversight of the Task Group on Data and Scenario Support for Impact and Climate Assessment (TGICA), • TGICA was established by the IPCC to facilitate wide availability of climate change-related data and scenarios to enable research and sharing of information across the three IPCC working groups.

24. Important Definitions Baseline/Reference The baseline (or reference) is any datum against which change is measured. It might be a "current baseline", in which case it represents observable, present-day conditions. It might also be a "future baseline", which is a projected future set of conditions excluding the driving factor of interest. Alternative interpretations of the reference conditions can give rise to multiple baselines. Forecast/Prediction When a projection is designated "most likely" it becomes a forecast or prediction. A forecast is often obtained using physically-based models, possibly a set of these, outputs of which can enable some level of confidence to be attached to projections. Scenario A scenario is a coherent, internally consistent and plausible description of a possible future state of the world (IPCC, 1994). It is not a forecast; rather, each scenario is one alternative image of how the future can unfold. A projection may serve as the raw material for a scenario, but scenarios often require additional information (e.g., about baseline conditions). A set of scenarios is often adopted to reflect, as well as possible, the range of uncertainty in projections. Other terms that have been used as synonyms for scenario are "characterization", "storyline" and "construction".

25. Climate Model Outputs There are two types of information from global climate models that may also be useful in describing the climatological baseline: reanalysis data and outputs from GCM and RCM simulations. Reanalysis Data • These are fine resolution gridded data which combine observations with simulated data from numerical models. • Through a process known as data assimilation. The procedure combines: - the observations (available only sparsely and irregularly over the globe), - along with data from satellites - and information from a previous model forecast • This is integrated forward by one time step (typically 6 hours) and combined with observational data for the corresponding period. • The result is a comprehensive and dynamically consistent three-dimensional gridded data set (the "analysis") which represents the best estimate of the state of the atmosphere at that time. • The assimilation process fills data voids with model predictions and provides a suite of • constrained estimates of unobserved quantities such as vertical motion, radiative fluxes, and precipitation. • Large quantities of past observational data that were used operationally as inputs to earlier versions of weather forecasting models have subsequently been "reanalysed“. The product is called ‘reanalysis’

26. Climate Observation Networks and Systems http://www.wmo.int/pages/themes/climate/climate_observation_networks_systems.php The more stringent requirements on observation networks and systems for monitoring climate, including the detection of climate change, has led to the development of special networks at • GCOS (Global Climate Observing System) • GCOS - Surface Network (GSN) • GCOS Reference Upper-Air Network (GRUAN) • OceanSITES?: OceanSITES is a worldwide system of long-term, deepwater reference stations measuring dozens of variables and monitoring the full depth of the ocean from air-sea interactions down to 5,000 meters. • What is Argo?: Argo is a global array of 3,000 free-drifting profiling floats that measures the temperature and salinity of the upper 2000 m of the ocean. • GPCP: mature global precipitation product that uses multiple sources of observations, including surface information and satellites. GPCP product at 1 × 1 degree resolution daily estimates. • Climate Field Projects (Observational Networks) • TELEX, BAMEX, South American Monsoon Experiment (SAME), African Monsoon Multidisciplinary Analysis (AMMA)

27. Topic– Mean state of the atmosphere – global temperature (seasonal variability), geopotential height, general circulation (wind, pressure, climatological features), variability of the general circulation, precipitation, cloudiness

28. Topic - Mean State of the Atmosphere Idealized General Circulation on a Rotating Planet • Single-cell assumptions, but Earth rotates (Hadley’s mode) • Each hemisphere is divided into three pressure cells • Hadley Cells • Ferrell Cells • Polar Cells • One of each of these cells exist in each hemisphere

29. ITCZ and the Trade Winds • Similar form to the idealized pattern • Migrates approximately 10-20o from equator • Migrates little over areas affected by cold currents • Trade winds as well as ITCZ migrate equatorward during the cool season when thermal contrasts are maximized

30. Major cells: • Bermude-Azores high (North Atlantic) • Hawaiian high (North Pacific) • South Pacific High (Southern Pacific) • South Atlantic high (South Atlantic • Indian Ocean high (Indian Ocean)

31. Topic – Mean state of the oceans – temperature (horizontal and vertical), temperature variability, salinity, surface circulation; thermohaline circulation)

32. Ekman Spiral Effect Atmospheric Circulation 1:Wind 2:Force from above 3:Effective direction of the current 4: Coriolis effect

33. Topic – Mean state of the Oceans CirculationOcean Circulation • The momentum involved in moving that surface column of water > transferred downward to the next few meters of water, with > increasing friction and therefore a > decrease in CE • The result is a spiral of water motion extending from the surface downward to a depth of approximately 100 m – the Ekman spiral

34. Ocean CirculationSurface Currents • The circulation around these anticyclones initiate corresponding surface water motions in the oceans • These circular flows, caused by a coupling of the atmospheric and oceanic circulations, are called gyres

35. Ocean CirculationSurface Currents • The large scale motions of the oceanic surface ensures that cold currents occupy the eastern side of oceanic basins and warm currents are found along the western edges of the basins • Upwelling reinforces the effect of the cold currents along the eastern ocean basins. • When water is pushed against the coastline, or two ocean currents meet, downwelling occurs – usually on the eastern side of continents • Downwelling typically supports high ocean temperatures

36. Deep Ocean Thermohaline Circulations • Deep water currents are partly driven by surface currents • Precipitation characteristics of both the ocean and the surrounding land masses influence the density of ocean waters

37. Topic: Exchange processes between the surface and the atmosphere • Planetary boundary layer, • Stability considerations, • Hydrologic cycle

38. The laminar layer • Supports smooth atmospheric flow and is within a few millimeters at most) of the surface or elements on the surface • The roughness layer • Characterized by a large component of vertical motion compared to horizontal motion caused by mechanical turbulence • Also site of thermal turbulence

39. Definitions • Environmental lapse rate” (γ) • Laminar, roughness, and transition layers comprise the planetary boundary layer (PBL) • Which of the primary forces dominate in each layer-pressure gradient force, Coriolis effect, centrifugal force, geostrophic balance & frictional force • Relative humidity, vapor pressure (e), saturation vapor pressure (es) • What is the Clausius-Clapeyron equation (descriptive) • Dewpoint temperature (Td), Absolute humidity, Specific humidity (q), evapotranspiration (ET) • Stable atmosphere; Positive buoyancy, unsaturated adiabatic lapse rate (UALR or Γu); saturated adiabatic lapse rate (SALR, or Γs); Potential temperature (θ)

40. Unsaturated Adiabatic Lapse Rates Under Various Atmospheric Conditions.

41. Saturated Adiabatic Lapse Rates Under Various Atmospheric Conditions.

42. The Global Hydrologic Cycle

43. Topic- Climate variability (natural) – Many time scales, ENSO, NAO, PNA, AMO, PDO, MJO, Milankovitch cycles, volcanic activity, solar variability, paleoclimatology • - Many time scales intra-seasonal to multi century Definitions, time scale of variability; and geographical regions where the phenomena is significant for explaining natural variability of climate • - Intraseasonal: Madden–Julian Oscillation (MJO) • - Interannual: El Niño–Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Pacific–North American teleconnection pattern (PNA), Atlantic Multidecadal Oscillation (AMO), Volcanic activity • - Decadal: Solar variability, Pacific Decadal Oscillation (PDO) • - MultiCentury (Paleoclimatology for past climates): Milankovitch cycles, Continental Drift (plate tectonics)

44. Global Framework for Climate Services (GFCS) • WCC-3 Recommendation • HLT Formation • HLT recommendations • GFCS implementation strategy

45. Topic- Climate variability (anthropogenic) – Evidence for, greenhouse gas trends, land use change, pollution and aerosol contributions

46. What drives changes in climate (Forcing Agents That Cause Climate Change)? • Greenhouse gases • Aerosols • Volcanic activities • Tectonic geological changes • Solar output changes

47. IPCC INTERNATIONAL PROCESS The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP) in 1988. The aim was, and remains, to provide an assessment of the understanding of all aspects of climate change, including how human activities can cause such changes and can be impacted by them.

48. Why IPCC Updates Every Few Years • 1. More recent monitoring of climate change • 2. More recent assessments of paleoclimate • 3. Improved understanding of climate change • 4. More refined emission scenarios (parallel version) • 5. Improved statistical analysis techniques • 6. Improved models • 7. Greater access to high performance computing • 8. Better treatment of decadal variability and prediction in IPCC OAGCMs • 9. Builds on lessons learned in AR4 • 10. Improved estimation of radiative forcing • 11. Other valid reasons exist

49. Detection-Attribution-Projections • Detection is the process of demonstrating that an observed change is significantly different (in a statistical sense) than can be explained by natural variability. • Attribution is the process of establishing cause and effect with some defined level of confidence, including the assessment of competing hypotheses. • Projections: Model generated climate conditions that are consistent with climate scenarios

50. The Projections of the Earth’s Future Climate • Scenario: A scenario is a coherent, internally consistent and plausible description of a possible future state of the world (IPCC, 1994). It is not a forecast; rather, each scenario is one alternative image of how the future can unfold. A projection may serve as the raw material for a scenario, but scenarios often require additional information (e.g., about baseline conditions). A set of scenarios is often adopted to reflect, as well as possible, the range of uncertainty in projections. Other terms that have been used as synonyms for scenario are "characterization", "storyline" and "construction • Model Projections are forced by the emission scenarios: IPCC Emissions Scenarios of the Special Report on Emissions Scenarios (IPCC-SRES)