Download Which of the following gases do not Melting sea ice could

17/06/2015
Why has Climate change not allready been
stopped?
Evidence from projections and observations
People have been concerned about the rise in
carbon dioxide in our atmosphere, the result of
human activity, since what period of time?
100%
Prof. Dr. Rik Leemans
Environmental Systems Analysis Group
Wageningen University
16th June 2015
1.
2.
3.
4.
18th
19th
20th
21th
century
century
century
century
0%
0%
1
2
0%
3
4
In 1896, Svante Arrhenius published the first study measuring how CO2 contributes to the greenhouse effect. CO2 warms the Earth by trapping heat near the surface, a bit like swaddling the planet in an extra blanket. Arrhenius also speculated about whether changes in atmospheric CO2 have contributed to long‐term variations in Earth’s climate. He made the link between burning fossil fuels and global warming, a link we are clearly seeing today.
Prof. Dr. Rik Leemans S1
Which of the following gases do not
trap heat (i.e. contribute to the
greenhouse effect)?
85%
Prof. Dr. Rik Leemans S2
We produce more than 30 billion tons of
carbon dioxide per year. Where does the
majority of it end up?
46%
1.
2.
3.
4.
Carbon dioxide
Nitrogen
Water vapour
Methane
8%
8%
0%
1
2
3
1. It is inhaled by trees for
photosynthesis.
2. It enters our oceans.
3. It lingers in the
atmosphere.
42%
13%
4
1
Heat‐trapping greenhouse gases absorb and emit radiation within the thermal infrared range. Water vapour, carbon dioxide and methane are Earth's most abundant greenhouse gases. Nitrogen, which makes up 80 percent of Earth's atmosphere, is not a greenhouse gas. This is because its molecules, which contain two atoms of the same element (nitrogen), are unaffected by infrared light.
2
Prof. Dr. Rik Leemans S3
In the 10,000 years before the start of the industrial
Revolution in 1750, carbon dioxide levels in the air rose by
less than 10 percent. Since then they’ve risen by:
3
Forty to 50 percent of the carbon dioxide stays in the air, and almost 30 percent is dissolved in the oceans. Scientists are not fully sure about the rest. They believe it is absorbed by forests, soil and crops.
Prof. Dr. Rik Leemans S4
Melting sea ice could raise sea level
by several meters.
68%
58%
1. True
2. False
1. 21 percent
2. 43 percent
3. 62 percent
42%
28%
4%
1
2
3
Since 1750, humans added 590 ± 75 billion tons of carbon to the atmosphere in the form of carbon dioxide. In 2012, 92 percent of all human‐produced carbon dioxide originated from burning coal, natural gas, oil and gasoline. In 1750 the Co2 concentration was c. 280 ppm. Now it is 400 ppm (i.e. a 43% increase).
Prof. Dr. Rik Leemans S5
1
2
Melting sea ice cannot raise global sea level since the ice is already floating. (Think of an ice cube melting in a glass full of water, which doesn't raise the water level.) However, Arctic sea ice is thinning and the long‐term summer average cover has decreased by 34 percent in 1979. Ice from glaciers and ice sheets, which form on land, does add water to Earth's oceans when it melts and does contribute to sea level rise.
Prof. Dr. Rik Leemans S6
1
17/06/2015
As average global temperature rises,
1. Average precipitation
increases
41%
2. Average precipitation
decreases
41%
1.
2.
3.
4.
5.
18%
3. Average precipitation is
unchanged
1
2
Where have some of the strongest
and earliest impacts of global
warming occurred?
3
A higher temperatures give rise to a more active water cycle, which means faster and greater evaporation and precipitation and more extreme weather events.
In the tropics
In northern latitudes
Over the oceans
Over mountains
global warming is distributed
equally all over the planet
36%
32%
25%
7%
0%
1
3
4
5
Some of the fastest‐warming regions on the planet include Alaska, Greenland and Siberia. These Arctic environments are highly sensitive to even small temperature increases, which can melt sea ice, ice sheet and permafrost, and lead to changes in Earth’s reflectance (or “albedo”).
Prof. Dr. Rik Leemans S7
http://www.skepticalscience.com/
2
Prof. Dr. Rik Leemans S8
Forecasts: Opiate for decision makers
http://www.theguardian.com/environment/climate‐consensus‐97‐per‐
cent/2013/oct/01/ipcc‐global‐warming‐projections‐accurate
Prof. Dr. Rik Leemans S9
Union of Concerned
Scientists Infographic
Prof. Dr. Rik Leemans S10
Eminent US climate scientist, Kevin Trenberth
The answer to the oft-asked question of whether an event is
caused by climate change is that it is the wrong question. All
weather events are affected by climate change because the
environment in which they occur is warmer and moister than it
used to be.
This calls on us to reframe how we think about human-induced climate
change. We can no longer place some events into the boxes marked
“Nature” and “Human”.
"It's not known for sure whether (a) climate change
is actually occurring or (b) if it is, whether humans
really have any influence on it." American Petroleum
Institute, 1998
"...current indirect CO2 benefits clearly outweigh
any hypothesized cost by literally orders of
magnitude; the benefit-cost ratios range up to more
than 200-to-1." Peabody Energy, 2014
Prof. Dr. Rik Leemans S11
Inventing these two boxes was the defining feature of modernity,
founded on Cartesian and Kantian philosophies. Climate science now
shows that such a separation can no longer be sustained, that the
natural and the human are mixed up, and their influences cannot be
neatly distinguished.
Trenberth, K.E., 2012: Framing the way to relate climate extremes
to climate change. Climatic Change, 115, 283-290.
Prof. Dr. Rik Leemans S12
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Temperature change in the SRES scenarios
Climate scenarios of the
Intergovernmental
Panel on Climate
Change (IPCC)
Prof. Dr. Rik Leemans S13
The IPCC scenarios: GHG emissions
Emphasis on material wealth
Emphasis on sustainability and equity
Complete globalisation
Strong regionalisation
Prof. Dr. Rik Leemans S15
Summary of IPCC SRES scenarios
Prof. Dr. Rik Leemans S14
The final figure from IPCC’s synthesis report
Emissions
Narratives
Climate change Impacts
Concentrations
Prof. Dr. Rik Leemans S16
New scenarios development process:
A time-saving parallel versus sequential approach
o Global GHG emissions increase in all scenarios in the
next 10-50 years
o After 2050, emissions can increase fivefold but also
be halved in world futures without climate policy
o GHG emissions are strongly related to developments
and policies in other areas than climate change
o Large co-benefits between sustainable development,
energy efficiency, land use and climate change
policies
Prof. Dr. Rik Leemans S17
Prof. Dr. Rik Leemans S18
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Representative Concentration Pathways
Representative Concentration Pathways
Representative Concentration Pathways (RCPs) are greenhouse gas
concentration trajectories (i.e. not emission scenarios like SRES)
adopted by the IPCC in 2014. The RCPs supersede the SRES
Scenarios (IPCC, 2000).
RCP8.5
The RCPs are used for climate modelling and research. They
describe four possible climate futures, all of which are considered
possible depending on how much greenhouse gases are emitted in
the years to come.
RCP6.0
The four RCPs (i.e. RCP2.6, RCP4.5, RCP6 and RCP8.5) are named
after a possible range of radiative forcing values in the year 2100
relative to pre-industrial values (i.e. +2.6, +4.5, +6.0, and +8.5
W/m2, respectively).
RCP4.5
RCP2.6
More information on:
http://www.theguardian.com/environment/climate-consensus-97per-cent/2013/aug/30/climate-change-rcp-handy-summary
Prof. Dr. Rik Leemans S19
Prof. Dr. Rik Leemans S20
Emissions that comply with the various
Representative Concentration Pathways
RCPs also provide opportunities for the longer
term
The 90th and 98th percentiles are indicated by the dark and light grey areas respectively.
http://www.iiasa.ac.at/web‐apps/tnt/RcpDb
Prof. Dr. Rik Leemans S22
Prof. Dr. Rik Leemans S21
The main effects of the different RCPs
Circles (●) : Scenario emissions growth over the period in horizontal axis
Crosses (X) : Historical emissions growth over the period in horizontal axis
Observed emission and the IPCC scenarios
Observed emission (X) follow the top
of all IPCC scenarios (●)
Brysse, Oreskes, O’Reilly & Oppenheimer, 2013. Climate change prediction: Erring on the side of least drama? Global Environmental Change (in press).
Prof. Dr. Rik Leemans S23
Prof. Dr. Rik Leemans S24
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If you removed the atmosphere's natural
Understanding
temperature
trends
greenhouse effect, and everything else stayed the
same, Earth's temperature would be:
1.
2.
3.
4.
6 to 11°C warmer
17 to 22°C warmer
6 to 11°C cooler
28 to 33°C cooler
52%
44%
4%
0%
1
2
3
4
The greenhouse effect is a naturally occurring physical process that warms the Earth's surface with energy from the atmosphere. Without the effect, Earth's average surface temperature would be well below freezing, i.e. 28 to 33°C cooler.
Prof. Dr. Rik Leemans S25
The six hottest years on record
occurred during the last:
67%
1. 100 years
2. 50 years
3. 10 years
Where have some of the strongest
and earliest impacts of global
warming occurred?
1.
2.
3.
4.
5.
26%
7%
1
Prof. Dr. Rik Leemans S26
2
3
According to NASA, 2009 was only a fraction of a degree cooler than 2005—the warmest year on record—and was tied with a cluster of other years—1998, 2002, 2003, 2006 and 2007—as the second warmest year since record‐keeping began. January 2000 to December 2009 was the warmest decade on record.
0%
1
0%
2
3
0%
4
0%
5
Some of the fastest‐warming regions on the planet include Alaska, Greenland and Siberia. These Arctic environments are highly sensitive to even small temperature increases, which can melt sea ice, ice sheet and permafrost, and lead to changes in Earth’s reflectance (or “albedo”).
Prof. Dr. Rik Leemans S27
No place on Earth is colder today
than it was 100 years ago.
100%
In the tropics
In northern latitudes
Over the oceans
Over mountains
global warming is distributed
equally all over the planet
Prof. Dr. Rik Leemans S28
Confusion on data
68%
1. True
2. False
32%
1
2
Although most locations on the planet have recorded increased temperatures since 1900, changes in global ocean and atmospheric circulation patterns have created small‐scale temperature decreases in a few local regions.
Prof. Dr. Rik Leemans S29
Prof. Dr. Rik Leemans S30
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Globally averaged increase in temperature anomaly
(oC from 1951-80)
Prof. Dr. Rik Leemans S31
Globally averaged increase in January-February
temperature anomaly (oC from 1951-80)
The temperature anomalies for
different latitudinal bands
Prof. Dr. Rik Leemans S32
Seasonal temperature anomalies
http://www.columbia.edu/~mhs119/Temperature/T_moreFigs/
Increasing temperatures are observed,
but what is/are the causes (i.e. explaining
the patterns or attribution of causes)
Prof. Dr. Rik Leemans S33
Prof. Dr. Rik Leemans S34
Does the long-term warming trend continue?
The hiatus
1998 - now
From: IPCC AR5
Prof. Dr. Rik Leemans S35
Prof. Dr. Rik Leemans S36
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The climate
hiatus
Climate sensitivity
Climate sensitivity is the equilibrium temperature change in
response to changes of the radiative forcing (or CO2
concentrations). The climate sensitivity depends on the initial
climate state. It can be inferred from palaeo-climate data,
observed temperature
change and climate
models. Slow feedbacks,
especially change of ice
sheet size and
atmospheric CO2, amplify
the total climate
sensitivity by an amount
that depends on the time
scale considered.
Some claim that after
1998 (a strong El Niño
year) the global mean
surface temperatures
have not increased
anymore. However, IPCC
shows that the nineties
were warmer than the
eighties, and the first
decade of this century is
warmer again than the
nineties.
The cost common value ranges from 1.5‐ 4.5oC at a doubling of CO2
Prof. Dr. Rik Leemans S37
The climate hiatus and natural variability
Natural variability is an important aspect of climate change. They
include volcanic eruptions, solar variability, dust storms, and ocean
circulation (El niño/La nina, PDO, NAO).
Prof. Dr. Rik Leemans S38
How much of Earth's surface is
covered by water?
88%
1.
2.
3.
4.
30%
50%
70%
85% or more
0%
1
2
3
4
Earth is often referred to as the "Water Planet" because you can see water in all three forms as you gaze at Earth from space. As we search for life elsewhere in the cosmos, we look for places that have liquid water, as it seems to be the primary requirement for life as we know it. About 70% of Earth is covered by water, and most of that water (97%) is found in our vast oceans.
Grant, F., and R. Stefan. 2011. Global temperature evolution 1979–2010. Environmental Research Letters 6:044022.
Prof. Dr. Rik Leemans S39
What role do the oceans play in the
carbon cycle?
Prof. Dr. Rik Leemans S40
What percentage of heat from global warming
has the ocean absorbed in the past 40 years?
48%
1. a major source of carbon
dioxide
2. a major absorber of
carbon dioxide
3. Both 1 and 2
4. Neither 1 nor 2
8%
4%
59%
37%
11%
1.
2.
3.
4.
11%
35%
56%
93%
30%
11%
4%
0%
1
2
3
4
1
Oceans both release carbon dioxide into the air and absorbs or stores it. One‐third of all carbon dioxide emitted by humanity has been absorbed by the world’s oceans. This is making them more acidic than they have been for tens of millions of years. Warmer oceans are less able to store carbon.
Prof. Dr. Rik Leemans S41
2
3
4
Water resists changes in temperature; it is slow to heat up and slow to cool down. In scientific terms, water has high heat capacity. This means that, so far, Earth's ocean has been able to absorb and hold a majority (i.e. 93%) of the heat from Earth's atmosphere.
Prof. Dr. Rik Leemans S42
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Increased heat in de Oceans (1022 Joules)
Where is the heat generated by
the ‘greenhouse’?
Prof. Dr. Rik Leemans S43
Effect of natural variability in de Pacific Ocean
(IPO)
Prof. Dr. Rik Leemans S44
Bias adjustments to the data
Data adjusted for:
o lack of data in polar regions, Africa,
Asia and Latin America
o Climate variability
o Ship measurements
o Ocean heat uptake
Estimated rate of warming:
0.086oC per decade and 0.116oC per
decade for 2000-2014 (IPCC: 0.039oC
per decade)
In periods with a positive (negative) IPO, the temperature
trend is positive (negative)
Prof. Dr. Rik Leemans S45
Prof. Dr. Rik Leemans S46
To stabilize CO2 concentrations in the
atmosphere, the emissions should be:
1. The increase in recent CO2
emission must be stopped
2. Current CO2 emissions must
reduced by 25%
3. Current CO2 emissions must
reduced by 50%
4. CO2 emissions must peak before
2020 and then be reduced by at
least 90% before 2050.
Understanding
how to keep the
temperature
trends within
the internationally
accepted 2oC
67%
17%
17%
0%
1
2
3
4
The greenhouse effect is a naturally occurring physical process that warms the Earth's surface with energy from the atmosphere. Without the effect, Earth's average surface temperature would be well below freezing, i.e. 28 to 33°C cooler.
Prof. Dr. Rik Leemans S47
Prof. Dr. Rik Leemans S48
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17/06/2015
What are the allowed future emissions if all
countries agree to the 2o target (i.e. the Copenhagen
accords)?
What are the current cumulative CO2 emissions in
GtC since 1870?
50%
Q1: What are the current cumulative CO2
emissions in GtC since 1870? 1.
2.
3.
4.
5.
Q2: What are the allowable future cumulative CO2 emissions in GtC?
150
300
450
600
750
GtC
GtC
GtC
GtC
GtC
22%
17%
6%
1
Prof. Dr. Rik Leemans S49
What are the allowable future cumulative CO2
emissions in GtC to keep temperatures within 2oC?
100
200
300
400
500
600
GtC
GtC
GtC
GtC
GtC
GtC
2
3
4
5
Prof. Dr. Rik Leemans S50
The urgency of emission reduction to
stay within the 2o target
IPCC 2013
1.
2.
3.
4.
5.
6.
6%
What are the allowed future emissions if all
countries agree to the 2o target (i.e. the
Copenhagen accords)?
Maximally allowable
emissions are 400 Gt C
28%
Current worldwide
annual emissions are
10.5 Gt C
20%
16%
12%
12%
12%
That is (400/10.5)
38 jaar of the current
emissions
(with a reduction of 3%
per year, still 75 year)
1
2
3
4
5
6
How do we distribute
these 400 Gt C between
countries, people and
generations?
450 Gt C
850 Gt C
Prof. Dr. Rik Leemans S51
Consider national differences!
Prof. Dr. Rik Leemans S52
If humans stopped emitting carbon
dioxide tomorrow, what would happen to
global temperatures?
1. They would immediately
begin to drop.
2. They would continue to
rise.
3. They would stop rising,
flatten out and then
drop.
When we stop all carbon emissions right now, the hundreds of billions of tons of CO2 that have been pumped into the atmosphere and absorbed by the oceans since the Industrial Revolution would continue to warm the planet. For how long? No one knows, but estimates range from hundreds to thousands of years.
Prof. Dr. Rik Leemans S53
Prof. Dr. Rik Leemans S54
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There can be long time lags between
scientific consensus and societal consensus
Sherwood, S. (2011). Science controversies past and present. Physics Today, 64, 39‐44. Prof. Dr. Rik Leemans S55
Climate policies will get strong support
from the Pope this week!
Prof. Dr. Rik Leemans S56
Conclusions
 The climate system consist of many interacting components
and its precise behaviour is complex and difficult to predict
 Although new scientific insights continue to emerge, science
has developed the necessary skills to understand and
predict the system’s course behaviour
 Human influence is unequivocal (c.f. IPCC) and global mean
temperature continues to increase
 Many societal actors do not accept this robust science
because of political, lobbyest and post-modern motivations:
“Science has become another opinion” or “Do you believe in climate
change?”
 To limit climate change to 2oC and address other globalchange challenges is not yet impossible but requires
political courage, guts and nowadays immediate action
Prof. Dr. Rik Leemans S57
Prof. Dr. Rik Leemans S58
Prof. Dr. Rik Leemans S59
10