stamford raffles lecture 2013

ZSL Science and Conservation Events Tuesday 18 June 2013

Stamford Raffles Lecture A very dangerous experiment with our planet

Professor Sir Brian Hoskins CBE FRS

Director of Grantham Institute for Climate Change Imperial College London

A very dangerous experiment with our planet

Brian Hoskins

Director, Grantham Institute for Climate Change, Imperial College London Professor of Meteorology, University of Reading

Carbon Dioxide Measurements over the past year

Mauna Loa, Hawaii

Carbon Dioxide Measurements since 1957

Mauna Loa, Hawaii

Temperature and greenhouse gases in past 650,000 y

proxy for temp

methane

carbon dioxide

nitrous oxide

today time

IPCC 2007

Presenter

Presentation Notes

Figure TS.1. Variations of deuterium (δD) in antarctic ice, which is a proxy for local temperature, and the atmospheric concentrations of the greenhouse gases carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in air trapped within the ice cores and from recent atmospheric measurements. Data cover 650,000 years and the shaded bands indicate current and previous interglacial warm periods. {Adapted from Figure 6.3}

The Energy Budget of the Earth

341 Wm-2

(water vapour), carbon dioxide, methane,…

Fourier (1827), Tyndall (1861)

The Energy Budget of the Earth The Greenhouse Effect

341 Wm-2

396

333

Carbon Dioxide in the Atmosphere

We can be very confident that this rise in carbon dioxide in the

atmosphere is due to the activities of humans

land use change

emissions of greenhouse gases,

principally by burning coal, oil & gas

If 100t of carbon dioxide is added to the atmosphere

atmospheric content will be 40t greater after 20 years

35t greater after 100 years

25t greater after 1000 years

Estimated causes of the current imbalance in the energy budget of Planet Earth

IPCC 2007

Presenter

Presentation Notes

Figure SPM.2. Global average radiative forcing (RF) estimates and ranges in 2005 for anthropogenic carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and other important agents and mechanisms, together with the typical geographical extent (spatial scale) of the forcing and the assessed level of scientific understanding (LOSU). The net anthropogenic radiative forcing and its range are also shown. These require summing asymmetric uncertainty estimates from the component terms, and cannot be obtained by simple addition. Additional forcing factors not included here are considered to have a very low LOSU. Volcanic aerosols contribute an additional natural forcing but are not included in this figure due to their episodic nature. The range for linear contrails does not include other possible effects of aviation on cloudiness. {2.9, Figure 2.20}

Global temperature

Global temperatures and 20 year running average

20-year Running average

°C

Other evidence of a warming climate

Global sea level

Satellite 1991-

National Snow & Ice Data Center

1979-2000 average

September 2012 Arctic sea ice

Natural & anthropogenic forcings 14 models 58 simulations

Natural forcings only 5 models 19 simulations

Evaluation of climate models on 20th century climate

Annual precipitation

Observation

Average of all models

Increase in solar flux

Increase in long-lived GHGs

Mean Temperature changes in models for changed conditions

height

latitude

IPCC AR4 WGp1 Ch8

Projections: globally averaged surface Temperature IPCC 2007

Projected changes for end of century – unconstrained emissions

Dec –Feb Temperature Dec –Feb precipitation

Decadal Temperature trends at end of 21st century (A1B)

Ed Hawkins

Swiss Temperature Series 1864-2003 (mean of 4 stations) Schär et al. 2004, Nature, 427, 332-336

2010 Russian Heat Wave Barriopedro 2011

Frequency of occurrence of local T anomalies/local standard deviation of T Hansen et al 2012

Extreme Summer Heat in the Past Decade

2012 US summer

Temperature ºF

Rain %

Cold winter extremes of the past few years

Winter 2009/10 Eurasian cold

16 Nov- 25 Dec 2010

Dec 2010 Record cold in UK

Acidification of the ocean:

Estimated change in oceanic pH since 1700

Some other Global Environmental Problems associated with Human Activity

/

Stratospheric Ozone Depletion

BAS Column ozone measurements 1956-2007 Satellite views of ozone hole 1996-2012

Future low-level Ozone concentration – 2090s

60-80 ppb 100-120

Vitousek (1994)

Sulphur deposition risen by 2-3

Aerosols: the Asian Brown Cloud

Drivers of Change in Biodiversity & Ecosystems Millennium Ecosystem Assessment

Presenter

Presentation Notes

Almost all of the key direct drivers of change in biodiversity and ecosystem services are either remaining constant in their impact or growing in impact in all of the MA Systems. MA Synthesis Figure 4.3. Main Direct Drivers of Change in Biodiversity and Ecosystems (CWG) The cell color indicates impact of each driver on biodiversity in each type of ecosystem over the past 50–100 years. High impact means that over the last century the particular driver has significantly altered biodiversity in that biome; low impact indicates that it has had little influence on biodiversity in the biome. The arrows indicate the trend in the driver. Horizontal arrows indicate a continuation of the current level of impact; diagonal and vertical arrows indicate progressively increasing trends in impact. Thus for example, if an ecosystem had experienced a very high impact of a particular driver in the past century (such as the impact of invasive species on islands), a horizontal arrow indicates that this very high impact is likely to continue. This Figure is based on expert opinion consistent with and based on the analysis of drivers of change in the various chapters of the assessment report of the MA Condition and Trends Working Group. The Figure presents global impacts and trends that may be different from those in specific regions.

The anthropogenic climate change problem

The impacts derived from climate models are what are likely to occur if we are lucky -

increasing chance of crossing thresholds in the climate &/or natural or social systems

Context: growing world population need for development changing diet increased demand for food, water & energy other global environmental changes Impacts: water supply flooding ecosystems agriculture coastal erosion & flooding health ecosystems

“Climate Disruption” rather than “Global Warming”

Tackling the climate change problem

By continuing to emit greenhouse gases to the atmosphere

we are performing a very dangerous experiment with planet Earth.

1. Adapt

2. Do something else to compensate: remove carbon dioxide from the atmosphere

reduce the sun’s energy reaching us

3. Move towards a drastic reduction of the emissions of greenhouse gases:

mitigation

What can we do?

Mitigation

UK Climate Change Bill (Nov 2008)

• Commitment for at least 80% reduction in carbon dioxide emissions by 2050 • Established system of legally binding 5-year “carbon budgets” • Established the Climate Change Committee (CCC) to advise, monitor & report

International UN Framework Convention on Climate Change Kyoto Protocol, Conference of the Parties, …Copenhagen, Cancun, Durban, Doha…. Pledged: make 2015 agreement to start in 2020

EU 20% emissions reduction from 1990 levels by 2020, 30/40% by 2030? 2050 objective 80-95%

Many state or national targets e.g. China

Mitigation: UK Climate Change Committee

01020304050607080

2000 2050 2100 2150 2200

GtC

O2e

Year

2016:4%

2016:3%low

2016:3%high

2016:1.5%

A1B

00.5

11.5

22.5

33.5

4

2000 2050 2100 2150 2200°C

abo

ve p

re-in

dust

rial

Year

2016:4%low

90th percentile

central modelestimate

10th pecentile

2 Criteria: 50:50 chance of not getting much above 2ºC negligible chance of getting to 4ºC

Global 50% reduction in CO2e emissions by 2050: 2.1-2.6 t CO2e per person

In UK: 80% reduction in CO2e emissions by 2050 -enshrined in UK law

The UK 80% Reduction Challenge

Concluding Comments

A dangerous experiment: By adding greenhouse gases to the atmosphere we are taking a large risk that climate change may make life very difficult for our species & others Uncertainties in likely changes in local and regional climate change & in how the natural world will cope with a changing climate lead to many questions for those concerned with the future of the natural world. Mitigation of climate change to levels that significantly reduce the risk are possible and are likely to be beneficial in many other respects.

A very dangerous experiment with our planet

Brian Hoskins

Director, Grantham Institute for Climate Change, Imperial College London Professor of Meteorology, University of Reading

Past climate variation on 50K and 5K time-scales: Greenland ice accumulation rate

Jacobsen et al 2000

B1

A1B

A2

2011-30 2046-65 2080-99

Surface T projections for different periods and scenarios

IPCC 2003

“Geo-engineering” suggestions

Solar Radiation

Top ofAtmosphere

Surface

AerosolScattering

Cloud Albedo

Solar Interceptor

Grassland, Urbanization and Desert Albedo

Level 1 –Space

Level 2 –Stratosphere

Level 3 –Troposphere

Level 4 -Surface

2. Solar Radiation Management: reduce solar energy at surface

1. Carbon Dioxide Removal: remove from the atmosphere fertilise the ocean artificial trees, land surface treatment

Actual climate impact; other impacts; feasibility?

CCC (2012): the 5-year budgets & international aviation & shipping

CCC (2011): achieving the 2050 target

The Global Energy Budget

Greenhouse gases: water vapour, carbon dioxide, methane, ozone… Fourier (1827), Tyndall (1861),…

Global temperature

Some Feedbacks in the Climate System

Heat loss To space Water

vapour

Snow & ice

High cloud

Low cloud

Carbon flux

The atmosphere and oceans are fluids that move and interact

Projections: globally averaged surface warming

IPCC 2007 Different scenarios

Projected temperature in 80 years time

2060-99 (SRESA1B) – 1960-99 (20C3M)

Winter 850hPa zonal wind change T. Woollings 2010

The UK 80% Reduction Challenge

food, holidays

low C products

Solar, wind

walk/cycle, train/bus efficient cars

turn it off, use of water efficient boiler, fridge, TV, etc insulation, solar hot water

minimise waste & recycle

UK Climate Change Committee

• 50:50 chance of global temperature not rising much more than 2°C • Very small chance of rising 4°C

Global 50% reduction in carbon dioxide emissions by 2050: just over 2t per person per year

In UK: 80% reduction in carbon dioxide emissions by 2050

Used 2 criteria for global greenhouse gas emissions

Achieving targets: sensitivity to parameters

Warmest day

UKCP09: Change in summer temperatures in 2080s

Mean

10% 50% 90%

http://ukclimateprojections.defra.gov.uk/images/stories/Preprepared_maps/UK/UK_SumWarm_Lo_2080_10.png



http://ukclimateprojections.defra.gov.uk/images/stories/Preprepared_maps/UK/UK_SumTmean_Lo_2080_10.png



UKCP09: Change in summer precipitation in 2080s

Mean

Wettest day

10% 50% 90%

http://ukclimateprojections.defra.gov.uk/images/stories/Preprepared_maps/UK/UK_SumPmean_Lo_2080_10.png



http://ukclimateprojections.defra.gov.uk/images/stories/Preprepared_maps/UK/UK_SumWet_Lo_2080_10.png



ZSL Science and Conservation Events Tuesday 18 June 2013

Stamford Raffles Lecture A very dangerous experiment with our planet

Professor Sir Brian Hoskins CBE FRS

Director of Grantham Institute for Climate Change Imperial College London

stamford raffles lecture 2013

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