global warming: what we know now

Global WarmingScience New & Views, OLLI Sedona

Bob Haizmann

10/26/16

Global Warming

Effects• Atmospheric warming

• Ocean warming

• Ocean acidification

• Sea-ice decline

• Sea level increase

• Extreme weather

• Food security

Mitigation• Efficiency improvements

• Switch to non-fossil fuels

• Carbon pricing

• Political will

Causes• CO2 emissions from

burning coal, oil, gas, cement production

• CH4 from gas leaks & livestock farming

• N2O from fertilizers

• Fluorinated gases

• Reduced albedo from sea-ice decline

• Deforestation

Science News & Views presentation by Bob Haizmann, OLLI Sedona, Fall Quarter 2016

Evidence

• Ice core samples 800,000 years old show CO2 levels over time

• Earth's surface temperature has increased by 1.4℉ in the last 100 years, 1.0 ℉ in the last 30 years

• Satellite data • increase in global sea levels of 3 mm per year in recent decades

• decline in Arctic sea-ice extent 4% per decade; 50% lower in 2012 compared to 1979-200.


• Precession of Earth’s tilt - 26,000 years

• Obliquity - change in Earth’s axial tilt angle - 41,000 years

• Precession of Earth’s orbit around the Sun - 112,000 years

• Eccentricity of Earth’s orbit around the Sun– 100,000 years

• Tilt of Earth's orbital plane around the Sun - 100,000 years

Natural cycles change the climateMilankovitch Cycles


Tilt of Earth’s plane

Precession of orbit

Precession of tilt

Natural cycles change the climateMilankovitch Cycles

• When these cycles are in phase

they reinforce each other

• Hot and cold phases go through

100,000 yr cycles

• We should be entering a cooler

phase but this isn’t happening


CO2 and Global Temperatures –not dropping as in the past cycles


Last 400,000 years Last 1,000 years

CO2 range from ~190 - 280 ppm,

400,000 year average ~240 ppm

CO2 now 150 ppm above

400,000 year average

Energy consumption


Energy consumptionEnergy use per capita


Energy consumptionEnergy intensity – energy use per $ Gross Domestic Product


Energy consumptionUSA - change of energy consumption per GDP over time

• USA is getting more efficient, but not fast enough

• Tremendous economic growth has occurred while

getting more efficient


Paris agreement on climate change

• Sept 23, 2016 • USA with China announce they will formally

ratify the Paris Climate Agreement

• Together, they create 38 % world’s emissions

• USA pledged to cut emissions between 26 and 28 % vs 2005 levels by 2025

• Oct 4, 2106

• Ratification by the EU this month pushed it over a crucial threshold —approval of nations accounting for 55 percent of global greenhouse gas emissions

• Nov 4, 2016

• The Paris Agreement will enter into force


CO2 Emissions and Global Temperature Rise Constrained by Paris Agreement

Goal of Paris agreementGoal of Paris agreement

Current


USA Corporate Average Fuel Economy Plans CAFE standards

• 1978• Workarounds caused 20 years of

stagnation

• Example - light trucks had lower standards….birth of the SUV

• 2009• By 2017 - 35.5 mpg

• 2012• By 2025 – 54.5 mpg


USA Clean Power Plan

• August 3, 2015• President Obama and EPA announced the Clean

Power Plan

• Reduce CO2 by 30% by 2030 by shifting power generation to natural gas or renewables

• February 9, 2016• The Supreme Court stayed implementation of the

Clean Power Plan pending judicial review

• September 27, 2016• Lawyers for states & businesses reliant on coal

testified to a federal appeals court


The spiral of silence

• Few Americans, even those who care about the carbon crisis, chat about climate change with friends or family

• No one talks, so no one feels comfortable talking

• Silence begets silence widening the gap between popular discourse and public opinion, in an ever-descending spiral

http://climatecommunication.yale.edu/wp-content/uploads/2016/09/Climate-Spiral-Silence-March-2016.pdf

Science News & Views, presentation by Bob Haizmann, OLLI Sedona, Fall Quarter 2016

http://climatecommunication.yale.edu/wp-content/uploads/2016/09/Climate-Spiral-Silence-March-2016.pdf

global warming: what we know now

Environment