Het veranderend klimaat
Thomas Röckmann
Institute for Marine and Atmospheric Research Utrecht (IMAU)
Utrecht University
HOVO cursus 2009
College 2: Recente veranderingen in de atmosfeer
Atmosfeer en klimaat
HOVO cursus 2009
Natuurlijke en mens-gemaakte veranderingen in de atmosfeer De koolstofcyclus
De stijging van CO2 en andere gassen in het 20e eeuw Het “anthropoceen”
NEEM pictures
Temperature and trace gases from ice cores
IPCC, 2007
Temperatur und Spurengase II
IPCC 2001
CO 2 in the past
From IPCC 2007
A simple view of the Carbon cycle
gas exchange
90 90
Biosphere
plants 600 PgC soils 1600 PgC
plant assimilation
120
plant soil respiration
60 60
Atmosphere
760 PgC (~380 ppm)
Ocean
surface 1000 PgC deep 38000 PgC
Fossil fuels 4000 PgC
Units:
Reservoirs PgC (1015 gC) Fluxes PgC per year
6
http://cdiac.esd.ornl.gov/trends/emis/tre_glob.htm
Eerste stap: Nauwkeurige waarnemingen
Tweede stap: Verklaring, begrip van het systeem
->onderzoek naar globale kringlopen/budgetten
Global measurement network
CO2 rug
Waarnemigen in de atmosfeer
Stijging: ~30 ppb in 20 jaren
1.5 ppb/yr 3 PgC/y
“Airborne fraction”
From IPCC 2007
Emissies van fossiele brandstoffen
2 keer groter dan atmosferische stijging
Waar zijn de emissies?
From IPCC 2007
Op het noordelijke halfrond!
Koolstof isotopen
6 protonen 6 neutronen
12C +
6 protonen 7 neutronen
13C +
2 extra neutronen: 14C, radioactief
Isotope effects
CO2
13CO2
CnH2nOn
13CCn-1H2nOn
12
CO
2is assimilated faster than
13CO
213
CO
2is depleted in the plant by about 2%
Fossil material has no
14C
Sources: Friedli (1986), Francey (1999 ), and ESRL & INSTAAR, from P. Tans, NOAA/GMD
13 C observations
Extra CO
2is not from the ocean!
Δ 14 C observations
atmosphere
upper ocean
Extra CO 2 is not modern!
from P. Tans, NOAA/GMD
CONCLUSIES
De stijging van CO
2is (~)100% anthropogeen
Biosphere
source Ocean
source Anthropogenic source
Size of reservoirs - ? +
Size of fossil emissions (airborne fraction 50%)
- - +
Interhemispheric gradient ? - +
δ13C + - +
14C - ? +
Variability in 650.000 years - - +
Units: PgC (1015 gC) and PgC per year
Fossil fuels
5000-10000
plant assimilation
120 + 3?
landuse change plant soil
respiration
60 fossil fuel
burning
6
gas exchange
90 92
Surface ocean 1000 increase: 1
Deep ocean 38000 increase: 1
Sediments 0.2
Biosphere
2200
plants 600, soils 1600
Atmosphere 750 increase: 3
Rivers 1 60
2 ?
from I. Levin, IUP Heidelberg
Global CO
2cycle
Changes to the atmospheric CO
2budget
IPCC 2007
Nog twee voorbeelden
Het gemiddelde EU-Auto produceert 160 g CO2/km
-> Als je tussen de 6 en 10 keer je auto voltankt produceer je net zo veel kg CO2 als je auto weegt -> als je 10 km rijdt wordt zo veel CO2
geproduceerd dat de hele
atmosferische kolom boven 1cm2
aardoppervlakte 100% vol zit met CO2
2) CO2 climate forcing
provides more energy each year than has EVER been
produced from fossil fuels in the 250 years since the
industrial revolution.
This enormous amount of
energy is bound to impact the climate system.
The CO
2climate forcing is 1.7 W/m
21) The global energy consumption today is 0.03 W/m2
Methaanstijging
Bron: NOAA/CMDL, Boulder, en Etheridge et al., 1998
The last 20 years
Quellen [ Tg / yr ]
Senken [Tg / yr]
troposphärisches OH Transport in
Stratosphäre
Oxidation in Böden
499-558 12-31 39-49
Mülldeponien Wiederkäuer
Reisfelder
Energie
Natürliche Quellen Biomassen
Verbrennung
175-242
92-140
36-48
90-110 90-120
40-66
Quellen [ Tg / yr ]
Sources and sinks of atmospheric CH4 1990 – 2000
Atmospheric life time ~ 10 years
wetlands termites Ocean hydrates Total~ 600 Tg(CH4/y)
Biomass burning
Natural sources
Energy Domestic waste
Ruminants Rice paddies
Transport to
stratosphere Oxidation
in soils
Tropospheric OH
Sources [Tg/yr] Sinks [Tg/yr]
Changes to the atmospheric CH 4 budget
IPCC 2007
Identification of the “modern” N
2O source
present trend: +0.8 ppb/yr
pre-industrial
today
Changes to the atmospheric N
2O budget
IPCC 2007
Broeikasgassen en stralingsbalans IPCC bericht 2007
CO2 N2O
CH4
Bron: IPCC 2007
The anthropocene
Paul Crutzen, Nobel Price for Chemistry 1995 Most cited author in Geosciences 2002
“Since the beginning of the 19th Century, by its own growing activities, Mankind opened a new geological era:
the Anthropocene
Man is clearly affecting climate and is even able to deliberately do so.”
• During the past 3 centuries human population has increased tenfold to >6000 million and fourfold in the 20th century
• Cattle population increased to 1400 million (one cow/family); by a factor of 4 during the past century
• Urbanisation grew more than tenfold in the past century; almost half of the people live in cities and megacities
• Industrial output increased 40 times during the past century;
energy use 16 times
• Almost 50 % of the land surface has been transformed by human action
• Water use increased 9 fold during the past century to 800 m3 per capita; 65 % for irrigation, 25 % industry, ~10 % households
