Climate and climate modelling

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Climate and climate modelling

  1. 1. Pabitra Gurung PhD Student gurung@unbc.ca NRES 804 CLIMATE AND CLIMATE MODELLING
  2. 2. OUTLINE  Climate and Climate Modelling  Global Climate Models / General Circulation Models (GCMs)  Regional Climate Models (RCMs)  Intergovernmental Panel on Climate Change (IPCC)  Projected Changes (IPCC, AR5)
  3. 3. Are you planning to use “Climate and Climate Change” information in your research? Is it an important for your study or not?
  4. 4. CLIMATE AND CLIMATE MODELLING (Source: IPCC, 2007 )
  5. 5. Forcing agents  Greenhouse Gases (CO2, CH4, N2O, O3, CFCs)  Aerosols (SO4, Carbon, Nitrate, Dust etc.)  Land use and Land Cover  Solar  Volcano  etc. Factors that change the climate (Source: IPCC, 2013 ) Sources/Actors: People, Industry, Agriculture, Urbanization, Vehicles, Disaster etc.
  6. 6. Important 5 components to understand climate models 1. Solar Radiation (absorbed by the atmosphere and sea) 2. Dynamics (e.g. movement of energy/heat and mass by winds) 3. Surface processes (effects of ice, snow, vegetation, albedo, and moisture interchanges) (Source: McGuffie and Henderson-Sellers, 2005)
  7. 7. Important 5 components to understand climate models 4. Chemistry (Chemical composition of atmosphere and interactions, e.g. CO2 exchanges between sea, land and atmosphere) 5. Resolution in both time and space (the timestep of the model and horizontal & vertical scales resolved) Note: Model setup & programming language and platform (Source: McGuffie and Henderson-Sellers, 2005)
  8. 8. Basic 4 types of climate model 1. Energy balance models (EBMs) (Surface temperature as a function of the energy balance on the Earth) 2. One-dimensional radiative- convective (RC) models (the temperature profile based on the modelling of radiative and a ‘convective adjustment’ which depend on the predetermined lapse rate ) (Source: McGuffie and Henderson-Sellers, 2005)
  9. 9. Basic 4 types of climate model 3. Dimensionally-constrained models (Statistical dynamical (SD) models, which deal with surface processes and dynamics) 4. Global climate models (GCMs) (3-dimensional nature of the atmosphere and ocean is incorporated) (Source: McGuffie and Henderson-Sellers, 2005)
  10. 10. A GCMs, a type of climate model, is a mathematical model of the general circulation of a atmosphere and ocean; and based on the Navier–Stokes equations on a rotating sphere with thermodynamic terms for various energy sources (radiation, latent heat). 𝜌 𝐷𝑣 𝐷𝑡 = 𝛻𝑝 + 𝜇𝛻2 𝑣 + 𝑓 (Where, “𝜌” is a density; “𝑣” is a flow speed; “𝑡” is a time; “𝑝” is a pressure; “𝜇” is a dynamic viscosity; and “𝑓” is a body forces) GLOBAL CLIMATE MODELS (GCMS) (Source: McGuffie and Henderson-Sellers, 2005; Spencer, 2009)
  11. 11. 1. Conservation of energy (the first law of thermodynamics) i.e. Input energy = Increase in internal energy + Work done 2. Conservation of momentum (Newton’s second law of motion) i.e. Force = Mass × Acceleration GLOBAL CLIMATE MODELS (GCMS) (Source: McGuffie and Henderson-Sellers, 2005; Islam, 2013) Fundamental 4-laws considered in GCMs
  12. 12. 3. Conservation of mass (the continuity equation) 𝜕𝜌 𝜕𝑡 + 𝜕𝜌 𝜕𝑥 𝑢 𝑥 + 𝜕𝜌 𝜕𝑦 𝑢 𝑦+ 𝜕𝜌 𝜕𝑧 𝑢 𝑧 = 0 (Where, “𝜌” is a density; “𝑡” is a time; “𝑥, 𝑦, 𝑧” are the three orthogonal directions; and “𝑢” is a flow speed) GLOBAL CLIMATE MODELS (GCMS) (Source: McGuffie and Henderson-Sellers, 2005; Islam, 2013) 4. Ideal gas law (an approximation to the equation of state – atmosphere only) i.e. Pressure × Volume ∞ Absolute temperature × Density Fundamental 4-laws considered in GCMs
  13. 13. There are seven primitive equations for all models, with the prognostic equations being energy (temperature), moisture (water), the wind components (u, v, w), mass (air density, and pressure). GLOBAL CLIMATE MODELS (GCMS) (Source: McGuffie and Henderson-Sellers, 2005; Islam, 2013) Fundamental 4-laws considered in GCMs
  14. 14. Types of GCMs 1. AGCM (Atmospheric GCM) Atmosphere and impose sea surface temperature 2. OGCM (Ocean GCM) Global sea patterns 3. AOGCM (Atmosphere and Ocean GCM) or CGCM (Coupled GCM) Coupled atmosphere-ocean models (e.g. CCSM4, HadCM3, GFDL) GLOBAL CLIMATE MODELS (GCMS) (Source: McGuffie and Henderson-Sellers, 2005; Islam, 2013)
  15. 15. REGIONAL CLIMATE MODELS (RCMs) (Source: Feser et al., 2011; Giorgi, 2008) RCMs are tools used to achieve high-resolution climate data from coarsely resolved GCMs.
  16. 16.  Higher detail for mountain ranges and coastal zones  More detail on differing vegetation coverage and soil characteristics  A description of smaller-scale atmospheric processes To produce model output that is closer to the real heterogeneity condition (Physiographic details) of the nature. REGIONAL CLIMATE MODELS (RCMs) (Source: Evans, 2012; Feser et al., 2011; Wang et al., 2012) The added value of the RCMs in comparison with the GCMs
  17. 17.  Higher detail for mountain ranges and coastal zones  More detail on differing vegetation coverage and soil characteristics  A description of smaller-scale atmospheric processes To produce model output that is closer to the real heterogeneity condition (Physiographic details) of the nature. REGIONAL CLIMATE MODELS (RCMs) The added value of the RCMs in comparison with the GCMs (Source: Evans, 2012; Feser et al., 2011; Wang et al., 2012) Temperature Anomaly
  18. 18. Development of Climate Model  Mid-1970s  Mid-1980s  First Assessment Report 1990 (FAR)  Second Assessment Report 1995 (SAR)  Third Assessment Report 2001 (TAR)  Fourth Assessment Report 2007 (AR4)  Fifth Assessment Report 2013 (AR5) INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC) (Source: IPCC, 2013 )
  19. 19.  Representative Concentration Pathway (RCP) 1. RCP2.6 2. RCP4.5 3. RCP6.0 4. RCP8.5  Reference Period (1986-2005)  Projected Period (2016-2035, 2046-2065, 2081-2100, ... ) Projection Scenarios (AR5) (Source: IPCC, 2013 )
  20. 20. Global Mean (5% - 95% model ranges) 2046-2065 2081-2100 Scenario Mean Range Mean Range RCP2.6 1.0 0.4 - 1.6 1.0 0.3 - 1.7 RCP4.5 1.4 0.9 - 2.0 1.8 1.1 - 2.6 RCP6.0 1.3 0.8 - 1.8 2.2 1.4 - 3.1 RCP8.5 2.0 1.4 - 2.6 3.7 2.6 - 4.8 Projected Changes in Temperature (°C) (Source: IPCC, 2013 ) PROJECTED CHANGES (IPCC, AR5) Note: Reference/Baseline period: 1986-2005
  21. 21. (Source: IPCC, 2013 ) Projected Changes in Precipitation (IPCC, AR5)
  22. 22. (Source: IPCC, 2013 ) Projected Changes in Sea Level (IPCC, AR5)
  23. 23. Questions ?
  24. 24. REFERENCES Evans, J.P., 2012. Regional Climate Modelling: The Future for Climate Change Impacts and Adaptation Research. Earthzine. http://www.earthzine.org/2012/02/14/regional-climate-modelling-the-future-for-climate-change-impacts-and- adaptation-research/. Accessed 7 Mar 2014. Feser, F., B. Rockel, H. von Storch, J. Winterfeldt, and M. Zahn, 2011. Regional Climate Models Add Value to Global Model Data: A Review and Selected Examples. Bulletin of the American Meteorological Society 92:1181–1192. Giorgi, F., 2008. Regionalization of Climate Change Information for Impact Assessment and Adaptation. WMO Bulletin 57:86–92 IPCC, 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change S. Solomon, D. Qin, M. Manning, M. Marquis, K. Averyt, M. M. B. Tignor, and H. L. Miller (Editors). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. IPCC, 2013. The Physical Science Basis Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. T. F. Stocker, D. QIN, G.-K. Plattner, M. M. B. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex, and P. M. Midgley (Editors). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Islam, S. U., 2013. Role of Modeling and Simulation in Climate Predictions. Presentation at Climate Science Informal Seminars. University of Northern British Columbia. McGuffie, K. and A. Henderson-Sellers, 2005. A Climate Modelling Primer. John Wiley & Sons, Ltd, Chichester, England. Spencer, R.W., 2009. How Do Climate Models Work? Global Warming. http://www.drroyspencer.com/2009/07/how-do- climate-models-work/. Accessed 7 Mar 2014. Wang, T., A. Hamann, D.L. Spittlehouse, and T.Q. Murdock, 2012. ClimateWNA—High-Resolution Spatial Climate Data for Western North America. Journal of Applied Meteorology and Climatology 51:16–29.

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