Climate Change: Current State of the Science and Impacts

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1 Climate Change: Current State of the Science and Impacts Lloyd A. Treinish IBM Distinguished Engineer Chief Scientist, Environmental Modelling, Climate and Weather IBM Thomas J. Watson Research Center Yorktown Heights, NY

2 2 Climate Change: Current State of the Science and Impacts Recent scientific results Interesting business use cases Implications for regional and local scale modelling Questions for the panelists

3 Recent Scientific Assessments for Climate Change Global annually averaged surface air temperature has increased by about 1.0 C over the last 115 years (1901 to 2016) This period is now the warmest in the history of modern civilization Over the next few decades (2021 to 2050), annual average temperatures are expected to rise by about 4.5 C for the United States Source: U.S. Global Change Research Program, 3

4 Recent Scientific Assessments for Climate Change Global average sea level has risen by about 7 to 8 inches since 1900 About 3 inches occurred since 1993 Global average sea levels are expected to continue to rise by at least several inches in the next 15 years and by 1 to 4 feet by 2100 A rise of as much as 8 feet by 2100 cannot be ruled out 4 Source: U.S. Global Change Research Program,

5 Future Climate Scenarios RCP: Representative Concentration Pathways Changes in radiative forcing in 2100 relative to pre-industrial conditions: +2.6, +4.5, +6.0 and +8.5 watts per square meter (W/m 2 ) A measure of the influence of GHGs, pollutants, etc. on the atmosphere RCP8.5 implies a future with continued high emissions growth, whereas the other RCPs represent different approaches to mitigating emissions 5 Source: Intergovernmental Panel on Climate Change (IPCC)

6 Direct Observations Attributed to a Changing Climate Beyond just warmer temperatures, sea level rise and loss of sea ice, Basic physics The atmosphere can hold 7% more water with each increase of temperature by 1 o C, on average (Clausius Clapeyron equation) Many temperature and precipitation extremes are becoming more common 1. The frequency of cold waves has decreased since the early 1900s in the US 2. The frequency and intensity of heat waves has increased since the mid-1960s in the US 3. The frequency and intensity of heavy precipitation events are increasing in the US since 1901, especially in the northeast The oceans are not just rising, they are warming and changing The world s oceans have absorbed about 93% of the excess heat caused by greenhouse gas warming since the mid-20th century The world s oceans are currently absorbing more than a quarter of the CO 2 emitted to the atmosphere annually from human activities, making them more acidic Oxygen levels are expected to decrease by as much as 3.5% (i.e., RCP8.5) 6 Source: U.S. Global Change Research Program,

7 7 16 Events in 2017 with Cumulative Impact of $306.2B

Billion Dollar Disaster Event Types by Year 8 219 Events from 1980 to 2017

8 Billion Dollar Disaster Event Types by Year Events from 1980 to 2017 with Cumulative Impact of $1.5T Adjusted by Consumer Price Index (Source: NOAA)

9 Climate Event Attribution What aspects of such events can be attributed to a changing climate? The US wildfire season is three months longer than in 1940 and more intense Tropical storms of greater intensity More flooding events due to precipitation of greater intensity and coastal storm surge Increased droughts What aspects of such events can not (yet?) be attributed to a changing climate? Tornadoes, hail and severe thunderstorms Winter storms Frequency of tropical storms What are some of the (known) unknowns (potential surprises)? Impacts from reduced polar ice Combinations of conditions (e.g., drought, heat waves and wildfire) 9 Source: U.S. Global Change Research Program,

10 10 Our Collective Situation Limiting globally averaged warming to 2 C will require major reductions in emissions Global mean atmospheric carbon dioxide concentration has now passed 400 ppm, a level that last occurred about 3 million years ago, when global average temperature and sea level were significantly higher than today Continued growth in emissions would lead to an atmospheric concentration not experienced in tens of millions of years The present-day emissions rate of nearly 10 Gigatons of Carbon per year suggests that there is no climate analog for this century any time in at least the last 50 million years Stabilizing global mean temperature to less than 2 C above pre-industrial levels requires substantial reductions in net global Cumulative global emissions must stay below about 800 Gigatons of Carbon in order to provide a two-thirds likelihood of preventing 2 C of warming Assuming global emissions are equal to or greater than those consistent with the RCP4.5 scenario, this cumulative carbon threshold would be exceeded in approximately two decades Source: U.S. Global Change Research Program,

Examples of Potential Economic Effects of Climate Change by 2100 11 Source:

11 Examples of Potential Economic Effects of Climate Change by Source: U.S. Government Accountability Office,

12 12 Energy infrastructure Viability of thermal power plants (e.g., sufficient water at low-enough temperature for cooling and/or steam generation) Viability of hydro-electric plans given water availability Increased demand for energy in a future climate (e.g., cooling in urban areas, pumping of water from longer distances) Mitigation of greater storm-driven damage Viability of wind and solar power given changes in weather and land use For example, reduction in wind power potential of 10% by 2050 and 18% by 2100 in the central US (and an increase of 21% by 2050 and 42% by 2100 in eastern Brazil) Aviation Implications of a Warming Climate Changes in routing, given potential for increased clear-air turbulence due to climate change Changing choice of aircraft given insufficient lift for regional jets in very warm conditions

13 13 Implications of a Warming Climate Urban planning (e.g., effectiveness of mitigation strategies) Mitigation of heat-island effects (e.g., length and magnitude of heat waves, reduction in energy use) by policy change (e.g., green roofs) Adaptation for coastal cities, given sea-level rise, increased risk for storm and tidal surgedriven flooding Mitigation of flash flooding from likely increase in convective storms Need to change storage and drainage for combined sewer systems given impacts of precipitation Water management (drought risk) Increased hydrologic risk due to changes in future water availability (i.e., precipitation, evaporation, runoff) vs. water demand

14 14 Agriculture Implications of a Warming Climate Lead time for seasonal planning (i.e., before a climate shock occurs), including extreme events, number of frost days, soil runoff in large rain events Ranching: long-term changes in viability of operations in semi-arid areas (precipitation; evapotranspiration; frequency of drought) Crop production: types of crops that can be grown in a changing climate; grains, trees and vine varieties (changing ecoregions; changes in monthly and seasonal precipitation; evapotranspiration; length of growing season) Fisheries: viability of species appropriate habitats in lakes and rivers (temperature; water temperature; streamflow; snowpack) Water management and the water, energy and food nexus: identifying the hydrologic risk using indicators of future water availability (i.e., precipitation, evaporation, runoff) vs. water demand Lost production can lead to rising food prices causing social unrest, while local crop failures can lead to migration

Implications of a Warming Climate Health Increased heat stress by considering the 35 o C wet bulb temperature threshold For example, 1M person-days per year by 2080 Increased incidence of various

and insect-vectored diseases such as malaria, dengue fever, zika, cholera, etc.

15 Implications of a Warming Climate Health Increased heat stress by considering the 35 o C wet bulb temperature threshold For example, 1M person-days per year by 2080 Increased incidence of various conditions given known relationships to temperature and pollution For example, 100K new cases of diabetes in the US for each 1 o C increase in temperature Impact of climate variability on water-borne and insect-vectored diseases such as malaria, dengue fever, zika, cholera, etc. Social and economic Given all of the above plus relationships between behavior and weather, a reduction of economic output is possible, at least 1-3% in the US alone (~0.7% per 1 o C) 15 In the US, there is significant inequality in this impact, where many of the poorer counties in the US would likely experience more adverse affects (~10 to 20% of GDP) Source: Estimating economic damage from climate change in the United States, Science 30 Jun 2017: Vol. 356, Issue 6345, pp Temperature Change ( o C) Relative to

16 16 Role for Regional- and Local-Scale Modelling Regional climate modelling can be used to evaluate characteristics of a changing climate on a more localized scale Results of such models can be used to adjust weather models to evaluate how environmental conditions may differ in a changed climate Such evaluations can be used to consider strategies to mitigate the impact of a changing climate, determine their effectiveness and to understand relative contributions of other factors (e.g., urbanization)

17 Approach to Regional Climate Modelling 1 Global Climate Model

Calibrated Regional Climate 4 2 Validation Effect of Mitigation

Observations (Past) 3 Global Climate Model (Future) Global

17 17 Approach to Regional Climate Modelling 1 Global Climate Model (Future) Global Re-Analysis (Past) Regional Climate Model (Future) Calibrated Regional Climate 4 2 Validation Effect of Mitigation Strategy Global Re-Analysis (Past) Regional Re- Analysis (Past) Observations (Past) 3 Global Climate Model (Future) Global Re-Analysis (Past) Mitigation (e.g., Green Roofs) Perturbed Regional Climate Model

18 18 Impact of Urban Expansion and Climate Change on Energy Demand Motivations To examine the impacts of a warmer climate and future expansion of urbanization in semi-arid regions (e.g., Phoenix and Tucson metropolitan areas) To estimate relative contributions of urbanization and climate change to future warming evaluate their impact on energy consumption Approach Compare 2070 to 2090 under RCP8.5 vs to 2005 (current climate) Compare 2070 to 2090 under RCP8.5 with different levels of urbanization Evaluate energy usage to drive air conditioning systems during summer months

19 Results for Tucson and Phoenix For areas already urbanized the increase in mean temperature will be approximately 3 to 3.5 C, almost completely due to climate change For new urbanized areas the increase of temperature will be approximately 4.5 to 5 C (~3 C from climate change and 1.5 to 2 C from urbanization) Cooling energy demand increases by 36% and 42% if both the urbanization a warm climate are considered Phoenix Tucson 19 Aggressive urbanization adds another 9% of cooling cost over least aggressive urbanization, especially due to increased density Increase due to global warming is relatively constant across the diurnal cycle

20 20 Urban Heat Islands and Heat Waves Due to Climate Change and Mitigation Strategies Motivations To examine the changes in the intensity of heat waves in a warmer climate and future expansion of urbanization (e.g., Phoenix and New York City metropolitan areas) To consider the effect of mitigation strategies under such heat waves Approach Compare 2070 to 2090 under RCP8.5 vs to 2005 (current climate) Compare 2070 to 2090 under RCP8.5 with cool roofs Compare 2070 to 2090 under RCP8.5 with green roofs

21 21 Results for New York City and Phoenix A warmer climate amplifies heat wave intensity in both Phoenix and NYC by 21% and 48%, respectively There was no significant change in intensity prior to the heat wave After the heat wave, Phoenix has a continued higher temperature, whereas NYC did not A warmer climate will intensify the interaction between urban heat islands and heat waves, especially in NYC, which can be mostly offset by adopting a green roof strategy The urban area is cooled by ~1.5 C in Phoenix and ~2.5 C in NYC Overall, green roofs are approximately three times more effective than cool roofs in NYC vs. two times for Phoenix Cool roofs are more effective during the day in both Phoenix and NYC In Phoenix, it is isolated to predominantly urban areas because surrounding rural areas tend to be cooler At night in NYC, the entire region, including rural areas, are cooler when green roofs are adopted

22 22 1. How does the latest science on our changing climate and projections of its impact affect preparations for potential extreme events and how we think about planning infrastructure? 2. What gaps exist in available information? Availability (public and private) Scale (spatial and temporal, including lead time) Fidelity (i.e., uncertainty) Handoff to the Panels Content (i.e., direct such as temperature vs impact) What risks can be addressed today? Given 2., what risks can not yet be addressed?

23 23 Lloyd A. Treinish IBM Distinguished Engineer IBM Thomas J. Watson Research Center IBM Analytics Solution Center

24 24 Backup Slides

25 25 IBM is Serious about Climate and the Environment Established a Corporate Policy on environmental affairs in 1971 Set and met three GHG emission reduction goals between 1990 and 2016 Avoiding 4.4 metric tons of CO 2 Conserving 7.2 TWh of electricity Established a Corporate view in 2006 that Climate change is one of the most critical global environmental challenges facing the planet Awarded the Gold Medal for International Corporate Achievement in Sustainable Development by The World Environment Center in 2012

26 26 IBM is Serious about Climate and the Environment Signed the American Business Act on Climate Pledge in 2015 Awarded a Climate Leadership Award by the US EPA, Center for Climate and Energy Solutions and the Climate Registry in 2017 Fifth time IBM has received this award Runs a number of programs supporting academic research In 2017 this included a call for proposals to leverage IBM s World Community Grid, data from The Weather Company, and cloud-based storage Pledged continued support for the Paris Climate Agreement in 2017

27 IBM Global Weather and Environmental Sciences Research and Development Team Andover: Atlanta: San Francisco: Forecasting Weather Underground Nowcasting Broadcast Visualization Austin: Flood modelling Weather modelling Aviation Broadcast Energy trading HPC Visualization Seasonal and sub-seasonal modelling Yorktown: Weather modelling Outages Renewables Environment Agriculture HPC Visualization Seasonal and climate modelling Ireland: China: Ocean/lake modelling Demand Forecasts Transportation Air pollution India: Kenya: Environment Agriculture Weather modelling Seasonal and climate modelling Air pollution Agriculture HPC Brazil: Weather modelling Hydrology and hydrodynamics Flood modelling Emergency management Australia: Cloud deployment Insurance Emergency management Mining We have weather-related research and development activities around the world 27

Committee on Energy Resources and the Environment

Committee on Energy Resources and the Environment CLIMATE SCIENCE S P E C I A L R E P O R T U.S. National Climate Assessment Volume 1: Summary of Findings Don Wuebbles Department of Atmospheric Sciences