Changing Climate and Increased Volatility What it Means for the Energy Sector in the Future April 3, 2014 Jeff Johnson, Chief Science Officer There is no doubt that the climate has changed, and it will continue to change. More importantly though, volatility has increased.
Topics What is climate? A century of warming Climate is inherently variable Natural causes of climate change Human influences on the climate system Changing volatility and extreme weather Impacts from increased climate volatility Outlook for the future Summary 2
What is Climate? Weather is represented by what the conditions of the atmosphere are over a short period of time Climate is the Average weather in a place over many years Climate represents a range of possible weather conditions Climate is dependent on forcing conditions, such as land/ocean, the sun, ice caps, rainforests, etc. This difference between weather and climate is a measure of time Climate is what you expect. Weather is what you get. 3
The Global Climate Has Warmed Earth s climate has always undergone changes Climate Change has been discussed and researched for several decades, but many questions remain about causes and effects The past century has shown a record of warmer temperatures on a global scale (1.4 0 F/.8 0 C) 4
Climate is Highly Variable Natural cycles on seasonal time scales impact the climate and produce natural variability El Nino/La Nina El Niño La Nina jet El Nino jet La Niña NAO 5
Climate is Highly Variable Natural cycles on yearly and multi-decadal time scales impact the climate Atlantic and Pacific Ocean Warm/Cold Phases Warm ATL warms NH AMO Index Solar Cycles Current cycle is weak Volcanism 1992 volcano cooling SO 2 from Mt. Pinatubo, 1991 6
AMO/PDO Cycles and Drought Atlantic & Pacific Ocean Cycles +PDO/-AMO +PDO/+AMO Pacific Ocean Atlantic Ocean -PDO/-AMO -PDO/+AMO Current phases http://www.pnas.org/content/101/12/4136.full.pdf 7
Human Activity Influences Climate Human behavior can influence regional climate change in several ways including land-use changes Deforestation, agriculture, urbanization change regional climate 1979-2003 Deg.C/Decade Increased drainage Change in Forest Extent 2000-12 8
Greenhouse gas emissions have increased over the past century GH Gases in Atmosphere Water Vapor - 95% CO 2-4% CO 2 is only very slowly removed by natural processes 9
Global Carbon Emissions 2009 Totals and Change From Previous Year http://www.guardian.co.uk/environment/2011/jan/31/pollution-carbon-emissions 10
What Does All This Mean For Now? Much has been learned about climate change, but many questions remain unsolved While there is evidence for warming over the past 100 years, model projections for the future have not worked out as well as expected A more important question has arisen surrounding increased volatility and extreme weather in recent years This could be a natural cycle or one that is also being influenced by human activities 11
Recent Increased Volatility Weather and Climate have become more volatile recently. Extreme weather events have become more frequent than natural variability would suggest Outlier events have occurred before, but recent events suggest a more active period These events have produced significant impacts as society faces greater risks from increasing exposure and vulnerability 12
Examples of Greater Volatility & Changes Warmer seasons are extended Increased incidence of extreme dryness or wetness More persistent periods of abnormally warm or cold weather Increased frequency of extreme rainfall events More concentrated periods of severe weather Extreme heat has increased, but extreme cold still occurs 13
Recent Increased Volatility Possible newly-linked reason: Polar regions have warmed the most, reducing the N/S temperature difference, which leads to: Jetstream patterns that are slower moving, blockier and more amplified, making anomalous weather patterns (e.g. heat waves, floods and droughts) more frequent Weaker Jetstream Warmer Last 10 years 14
Higher Pressure in the Arctic Region Over the Past Decade 15
Example of a Recent Blocking Pattern Winter 2013/14 Displaced cold Polar Vortex Warm blocking Upper Ridge 16
U.S. Annual Climate Extremes Index A way to quantify extreme weather occurrences Index =% of U.S. with: Max/min T extremes Drought 1 Day Rainfall extremes Days w-w/o rainfall 17
Percent of U.S. Experiencing Extreme Rainfall 18
Extreme Winter Cold Dropped Off After 1980 But then there was this past winter! 19
4-Day Heat/Cold Wave Trends (1 in 5 year occurrences) Heat Waves Are More Common, Cold Waves Are Less Frequent http://journals.ametsoc.org/doi/pdf/10.1175/bams-d-12-00066.1 20
Outliers Can Also Mean Very Quiet Periods Record Time Between U.S. Major Hurricane Landfalls (8-9 years) 2013 Was Very Quiet for Tornadoes 21
What Does the Future Hold? An increase in extended very warm or cold periods Winter cold in U.S. AK and Europe previous winters; very warm US 03/12. An increase in wildfires Hot, dry conditions increase the risk for wildfires. Western U.S. drought puts that area in greater danger. Increased flooding The 2007 IPCC report concludes that intense rain events have increased in frequency during the last 50 years. Land-use changes increase run-off. Increased drought The percentage of Earth's surface suffering drought has more than doubled since the 1970s. Drought is cyclical, and has been worse in the past. More intense hurricanes possible - but not yet a reality As the oceans warm, scientists predict that hurricane intensity could increase. Higher sea levels from warmer water make storm surges a greater risk to low-lying coastal cities. More Black Swan Events? The event is a surprise (to the observer). The event has a major effect. After the first recorded instance of the event, it is rationalized by hindsight, as if it could have been expected; that is, the relevant data were available but unaccounted for in risk mitigation programs. The same is true for the personal perception by individuals. Need to have greater imagination for the unexpected, big outlier events to occur (e.g. Sandy, NM/TX 2011 extreme cold, 100-500 year floods and storms) 22
Summary Fully understanding climate change is difficult and complex Sorting out natural vs. man-made influences is elusive Climate sensitivity to CO 2 is lower than projected More disruptive weather events are occurring There is a need for greater risk awareness for the probability of increased weather volatility and extreme weather Need to consider a longer time-horizon for extreme events Adaptation and preparation for greater risks is a reasonable course of action Expect the unexpected