Downloaded 91 times
More Related Content
Similar to Climate change and variability/ Abiodun Adeola
More from African Open Science Platform
Climate change and variability/ Abiodun Adeola
- 1. SA National ScienceWeek Theme: Facing the harsh realities of climate change 29 July-3 August 2019 Abiodun Adeola(PhD) Lead Scientist: Climate Change and Variability Thabo Makgoale Scientist: Climate Change and Variability South African Weather Service Climate change and variability
- 2.
- 3. First of all,you should know that weather and climate are not the same thing. Do you know?
- 4. WEATHER IS: • Shortterm • Limited area • Can change rapidly • Difficult to predict WEATHER is what’s happening outside your window right now. Definitions
- 5. CLIMATE IS: • Longterm (usually over 30-years) • Wide area • Seasonal changes • Measured over long spans of time CLIMATE is the average of many years of weather observation. Definitions
- 6. WEATHER: the stateof the atmosphere at a particular place and time as regards temperature, cloudiness, dryness, sunshine, wind, rain, etc. CLIMATE: the weather conditions prevailing in an area in general or over a long period usually over 30-years CLIMATE CHANGE: is a change in the statistical properties (principally its mean and spread) of the climate system when considered over long periods of time, regardless of cause Definitions
- 7. Climate Variability andClimate Change? CLIMATE VARIABILITY looks at changes that occur within smaller timeframes, such as a month, a season or a year, while CLIMATE CHANGE considers changes that occur over a longer period of time, typically over decades or longer.
- 8. ABIOTIC FACTORS: Latitude Altitude Ocean Currents Topography SolarRadiation Evaporation Orbital Variations Volcanic Activity BIOTIC FACTORS: Transpiration Respiration Photosynthesis Decomposition Digestion Climate forcing Climate is affected by many factors
- 9. A number ofgreenhouse gases occur naturally in the Earth’s atmosphere • Water vapor • Carbon dioxide • Methane • Nitrous oxide
- 10.
- 11.
- 14. Solar energy enteringEarth system ≈ 341 W.m-2 minus about 30% (≈ 102 W.m-2) reflected ≈ 239 W.m-2 Earth with an atmosphere Greenhouse gasses: Water vapour (H2O) Carbon dioxide (CO2) Methane (CH4) Greenhouse Warming 239 W.m-2239 W.m-2 Earth without an atmosphere The Greenhouse effect keeps the earth warmer than it would be if it did not have an atmosphere. With no greenhouse gases at all in its atmosphere, Earth’s average atmospheric temperature would be about -18° C Life (as we now know it) could not exist!
- 15.
- 16. The greenhouse gascontent of the atmosphere is being altered by human activity. The result of this change is global warming. e.g. Coal Mining, Deforestation, Burning of fossil fuels, Industrial processes, Agriculture Causes of Climate change
- 20. Global average temperaturechange since 1880 + 0.99 °C The graph illustrate the change in global surface temperature relative to 1951-1980 average temperatures. The 10 warmest years in the 136-year record all have occurred since 2000. Sources: TEMPERATURES: NASA (https://climate.nasa.giv/vital-signs/global- temperature) CO2: Ed Dlugokencky and Pieter Tans, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends/) -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 1.2 1880 1882 1884 1886 1888 1890 1892 1894 1896 1898 1900 1902 1904 1906 1908 1910 1912 1914 1916 1918 1920 1922 1924 1926 1928 1930 1932 1934 1936 1938 1940 1942 1944 1946 1948 1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 Temperatureanomaly(C) 300 320 340 360 380 400 420 1980 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009 2012 2015 GlobalCO2ppm Historic and currently observed climate can already provide substantial information about averages, extremes and trends. Note that these might differ from location to location Global Warming
- 21. Historical Global TemperatureTrends South Africa is warming at a slower rate if compared to other continental parts of the world - 1985 to 2014 global near-surface temperature trends (°C per decade). Source: NOAA’s National Climate Data Centre.
- 22. DANGERS OF CLIMATECHANGE
- 23. Dangers of Climatechange • Sea level rise • Extreme events • flooding, erosion, forest fires, wildfires, droughts, heat waves • Risk to human health • increase in number of heat- related and cold-related deaths, increase in infectious diseases • Risk for wildlife extinction • Loss of habitat and species • Imposes heavy cost on society and economy • agriculture, forestry, fisheries, tourism, infrastructure
- 24. WHAT CAN WEDO?
- 25. What can weDo? First we must admit that climate change is everyone’s problem. No agency, government, or scientist can “fix it” for us. We are all in this together. We got here because of our lifestyle. So our lifestyle has to change. Here’s what you can do…
- 30.
- 31. A future “view”on Climate Change
- 32. Following a “RotatingClimate Sensitive Route” Following a sustainable climate sensitive route Impact on climate sensitive sectors & elements Updates: Averages, Extremes, Frequencies Observe, Record, Monitor the environment Align to Forecasts, Predictions, projections. RESPOND, PLAN & ADAPT > Climate resilience Climate change adaptation can be achieved by following a sustainable ROTATING CLIMATE SENSITIVE ROUTE, based on good observations, regular updates and risk assessment and response planning according to observed weather and climate events, while aligning these to weather forecasts, seasonal predictions and climate change projections, as they happen at the location of interest. 1 2 3 4 Historical observations > confidence Future projections less confidence, but can be useful
- 33. Our Climate ComfortZone The atmosphere covers our bodies in all dimensions of space and time. Atmospheric properties that modulate temperature and moisture affect our entire existence on a daily basis. Atmospheric variability, expressed as weather and climate, not only supports out habitat, but can also bring devastation in its extremes. GLOBAL WARMING is a reality, and the risk that it poses to our climate comfort zone is a valid concern.
- 35. Climate terminology • Climate:Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. • Climate change: A change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcings, or to persistent anthropogenic changes in the composition of the atmosphere or in land use (IPCC 2012). • Climate extreme (extreme weather or climate event): The occurrence of a value of a weather or climate variable above (or below) a threshold value near the upper (or lower) ends of the range of observed values of the variable. For simplicity, both extreme weather events and extreme climate events are referred to collectively as ‘climate extremes.’ (IPCC 2012) • Climate forecast: The result of an attempt to produce an estimate of the actual evolution of the climate in the future, e.g., at seasonal, interannual or long-term time scales (IPCC 2007, WGII). • Climate model: A numerical representation of the climate system that is based on the physical, chemical, and biological properties of its components, their interactions, and feedback processes, and that accounts for all or some of its known properties. • Climate projection: A projection of the response of the climate system to emissions or concentration scenarios of greenhouse gases and aerosols, or radiative forcing scenarios, often based upon simulations by climate models. • Climate scenario: A plausible and often simplified representation of the future climate, based on an internally consistent set of climatological relationships that has been constructed for explicit use in investigating the potential consequences of anthropogenic climate change, often serving as input to impact models. Climate Glossary
- 36.