The science politics and economics of climate change

The science, politics and economics of climate change AQU Guest Al-Quds University, Abu Dis, Palestine

The topics of discussion The science • What is climate? • Observations of climate change. Politics of climate change • Which countries are responsible and who should pay? • Increasing greenhouse gases. • Are greenhouse gases really the explanation? • How is present different from the past? Impacts in Palestine Economics and climate change • How economic growth and climate change are intimately related. The psychology of (lack of) climate action • Extreme events and Health. • No clear external “enemy”. • Extreme events and Conflict. • We are all responsible. 2

First things first: Climate is different from weather 3

Climate vs weather Climate is different from weather • Climate: carry your rain jacket from December to February. • Weather: do you have to use your jacket on 20 th January? 4

Climate vs weather Climate is different from weather • Climate is average weather. 5

Observations of climate change 6

Observation of climate change Glacier retreat on “White Thunder Ridge”, Alaska 1941 2004 https: //nsidc. org/cryosphere/sotc/glacier_balance. html 7

Observation of climate change Glacier retreat in “South Cascade Glacier”, Washington 1928 2000 https: //nsidc. org/cryosphere/sotc/glacier_balance. html 8

Observation of climate change Arctic summer sea ice extent https: //climate. nasa. gov/news/2633/end-of-summer-arctic-sea-ice-extent-is-eighth-lowest-on-record/ 9

Observation of climate change Antarctic ice is reducing 0 Gt Ice mass - 2000 Gt 2002 Year 2017 Source: NASA satellite measurements (GRACE). 10

Observation of climate change Greenland ice is reducing even faster 0 Gt Ice mass - 4000 Gt 2002 Year 2017 Source: NASA satellite measurements (GRACE). 11

Observation of climate change Sea level rise from Satellite observations 80 Sea level rise (mm) 0 1993 Year 2016 Source: NASA Goddard Space Flight Center 12

Observation of climate change Extreme events are increasing worldwide. Munich Reinsurance Company 13

Observations of changing climate Global temperatures from 1880 to 2016 Temperature rise (o F) Year Data: NOAA 14

What are we humans doing? 15

What’s different today? Increase in greenhouse gases in the past 2000 years Methane (ppb) Carbon Dioxide (ppm) Nitrous Oxide (ppb) Carbon Dioxide Nitrous Oxide Methane IPCC 2007 16

What’s different today? Greenhouse gases cause heating (quantum mechanics) NASA graphic 17

Is the effect of greenhouse gases strong enough to explain current climate change? 18

Climate change attribution Climate change: natural variation or human intervention? • Natural variations: o Change in solar output? o Orbital changes? o Volcanic eruption? • Human intervention: o Forest -> Agriculture? o Aerosol injection? o Greenhouse gases? 19

Climate change attribution How does attribution work? Bloomberg graphics of climate change https: //www. bloomberg. com/graphics/2015 -whats-warming-the-world/ 20

Climate change attribution Recent rise in temperature cannot be explained without accounting for observed greenhouse change Temperature Rise (o. C) Adapted from Hegerl et. al. 2007. 21

How is climate change today different from the past? 22

It’s significant The speed of increase in CO 2 is the real problem 400 ppm 300 ppm CO 2 200 ppm 800, 000 years ago Source: Scripps Institution of Oceanography, USA Present day 23

Possible impacts in Palestine 24

Impacts The health concerns of heat waves in Palestine • Increase in mortality among infants and elderly people. • Agriculture – hence food security – is impacted by heat waves: malnutrition and undernutrition. • We urgently need research into extreme events and health impacts in Palestine. 25

Impacts Increasing droughts in dry parts of the World • General principle: “Dry becomes drier”. • Large parts of the West Bank are Arid. • Longer and more variable droughts may occur. Source: Palestine Hydrology Group 26

Impacts Conflicts over water Kelly et al, PNAS 112 (2015) 27

The problem: Increasing CO 2 concentrations due to emissions 28

Emissions CO 2 levels are already dangerously high 29

Who is responsible for this increase? Who should pay to “clean up”? 30

Emissions Yearly CO 2 emissions by selected countries. Annual CO 2 emission (Millions of tonnes) Data: Carbon Dioxide Information Analysis Center (CDIAC), Graphic: ourworldindata. org 31

Emissions Which countries have the largest CO 2 emissions person? CO 2 / person (tonnes) Source: UN Statistics Division, Millennium Development Goals Indicators 32

Emissions Cumulative CO 2 emissions by selected countries since 1750. Annual CO 2 emission (Millions of tonnes) Data: Carbon Dioxide Information Analysis Center (CDIAC), Graphic: ourworldindata. org 33

Emissions China emits a large amount of CO 2 producing goods for the rest of the World Davis, Caldeira PNAS 107 (2010) 34

Emissions China emits a large amount of CO 2, producing goods for the rest of the World Davis, Caldeira PNAS 107 (2010) 35

Infinite economic growth? 36

Emissions GDP and CO 2 emissions 37

Emissions What is economic development? • “The World GDP has returned to growth after the financial crisis. ” • “India’s GDP rose 5. 6%. ” • Growth in this way is an exponential function. • The assumption is that our economies must keep growing for development. 38

Emissions What is economic development? • Growth Increasing consumption uses physical resources. • In this perspective: economic growth has necessarily caused environmental damage: pollution and climate change. • The concept of infinite and increasingly faster economic growth based on natural resources on a planet with finite resources is flawed. 39

Emissions What are the alternatives? • Increases in efficiency? • Steady state economy? • Using other indicators than economic growth for human development: any merit to “Gross Happiness Index” used in Bhutan? • We may have to voluntarily reduce our consumption. 40

Why are we so bad at thinking about climate change? 41

Emissions Scientist and public opinions differ When the Science is Not Enough: Communicating the Consensus on Climate Change, PLOS, Sam Illingworth (2015) 42

Emissions The psychology of climate change (lack of) action • Climate change is gradual, hard to observe and indefinite in its eventual magnitude. • We have to make sacrifices today to prevent unclear costs in the future. • There is no clear enemy. 43

Emissions The psychology of climate change (lack of) action • We are to blame, and everyone we know: it’s in our self interest to discredit it or even deny it. • Green movements communicate individual responsibility, which can lead to resentment. 44

Emissions So how do we change that? • It is the health, economics and humans rights concerns of climate change that are more likely to motivation action. • Switch to renewable energy and sustainable living: worthy objectives irrespective of climate change. 45

Thank you 46

Supplementary slides 47

Observations of changing climate Global temperatures from 1850 to 2016 Data: Had. CRUT 4. 5, Visualization: Ed Hawkins 48

Impacts Heat wave intensity is increasing Data: Meehl et al, NOAA 49

Impacts Climate change is rapidly increasing the number of extreme events Ratio of extremes Data: Meehl et al, NOAA Year 50

How is past climate determined? 51

Paleoclimate Climate proxies Foraminifera Radiocarbon dating Tree rings Ice cores 52

Paleoclimate // radiocarbon dating 14 C is formed in the atmosphere and accumulates in organic tissues 53

Paleoclimate // radiocarbon dating 14 C decays in dead tissue 54

Paleoclimate // tree rings Tree rings: the number Number of rings tells us the age of the tree NASA Earth Observatory 55

Paleoclimate // tree rings Tree rings: their width Width of tree rings record annual rainfall Higher rainfall Drought NASA Earth Observatory 56

Paleoclimate // tree rings Annual rainfall for 1000 s of years in Sierra Nevada, Spain High rainfall Drought Hughes 1996 57

Paleoclimate // tree rings Events like forest fires can also be written in trees Fire scars NASA Earth Observatory 58

Paleoclimate // ice cores Ice cores as a climate proxy • Ice builds up incrementally. Deeper ice is older. • 18 O/16 O isotopic ratio is an indicator of temperature. • Composition of trapped air bubbles gives atmospheric composition. Google Earth Image 59

Paleoclimate // ice cores What do ice cores look like? Ice column Cross sections Fresh ice Old ice close to bottom Source: NASA Earth Observatory 60

Paleoclimate // ice cores Age of ice can be computed by counting seasonal layers Fresh ice Old ice close to bottom Source: NASA Earth Observatory 61

Paleoclimate // ice cores Age of ice can be computed by counting seasonal layers Source: NASA Earth Observatory 62

Paleoclimate // ice cores Ice also preserves temperatures Surface 0 500 Depth (m) 1000 1500 2000 Deep Colder Warmer 63

Paleoclimate // ice cores Temperature controls the isotopic ratio Distillation Principles of Planetary climate, R. Pierrehumbert 64

Paleoclimate // forams Climate record written into deep ocean • Year after year, fossils of plants and fish settle on ocean floor. • Vertical samples of ocean sediment yield millions of years of climate history! • Among these, fossils of forams, have proven most useful. 65

Paleoclimate // forams Forams • Forams are marine organisms that form Ca. CO 3 shells. • 18 O / 16 O isotopic ratio can reveal the temperature of the ocean. • Shells are enriched in heavy Oxygen in colder waters. 66

Paleoclimate // forams Sea Surface Temperature at peak of last ice age: 20, 000 years ago From ocean and lake sediment cores https: //earthobservatory. nasa. gov/Features/Paleoclimatology_Sediment. Cores/paleoclimatology_sediment_cores_2. php 67

Paleoclimate reconstruction Variations in the past 800, 000 years 68

Observation of climate change Arctic summer sea ice extent Source: http: //blogs. reading. ac. uk/climate-lab-book/files/2017/05/maparctic_sept. gif 69

Observations of changing climate Extreme events are increasing in the US. 70

Observations of changing climate Extreme events are increasing in China. 71

Paleoclimate // forams Reconstructed records for the past 500 million years. https: //earthobservatory. nasa. gov/Features/Paleoclimatology_Sediment. Cores/paleoclimatology_sediment_cores_2. php 72

Observations of changing climate Global temperatures from 1880 to 2016 relative to average for 1901 – 2000. Data and visualization: NOAA. 73

Observations of changing climate Past changes in global temperature Change in Temperature (o. C) Year IPCC 2007 74

Observations of changing climate CO 2 and temperature co-vary. Current CO 2 levels are highest in almost a million years. CO 2 (ppm) T (o. C) Source: Figure by Jeremy Shakun, data from Lüthi et al. , 2008 and Jouzel et al. , 2007. 75

Paleoclimate reconstruction Variations in the past 800, 000 years 76

Emissions China emits a large amount of CO 2 producing goods for the rest of the World Davis, Caldeira PNAS 107 (2010) 77

Emissions China emits a large amount of CO 2 producing goods for the rest of the World 78

Emissions China emits a large amount of CO 2 producing goods for the rest of the World 79

Climate impacts Intuitive explanation for why temperature extremes rise 80