CLIMATE AND ENVIRONMENTAL CHANGE M.Sc. Module ‚Global Transformation and Environmental Change‘

Prof. Dr. Jürgen Scheffran & Prof. Dr. Udo Schickhoff with slides provided by Prof. Dr. Jürgen Böhner Lecture 3

Prof. Dr. Jürgen Scheffran

Abteilung Integrative Geographie, Universität Hamburg Research Group Climate Change and Security Grindelberg 7, Room 2015 (Sprechstunde nach Vereinbarung)

Tel: 040 – 42838 7722 Email: [email protected] Web: www.clisec-hamburg.de

1 CLIMATE AND ENVIRONMENTAL CHANGE M.Sc. Module ‚Global Transformation and Environmental Change‘

Part A: Climate and Environment – Jürgen Scheffran I Introduction II The Climate System III Climate Change IV Environmental Change

Part B: Human Impact on World Vegetation – Udo Schickhoff

2 III CLIMATE CHANGE Indication & Reconstruction

Archives Overview

3 III CLIMATE CHANGE Indication & Reconstruction

Archives Overview

Archives (Proxy data) for the reconstruction of former (Paleo-) Climates and Climate Change (BRADLEY 1999)

T = Temperature

N = Precipitation

B = Biomass and Vegetation

V = Volcanic eruption

E = Terrestrial magnetic field

M = Sea-level fluctuations

C = Chemical composition

S = Solar radiation 4 III CLIMATE CHANGE Indication & Reconstruction

Archives Dating Methods

Radiocarbon dating: dating of carbonaceous organic material up to about 58 to 62 ka using the half-life of the radioactive carbon-14 (14C) Oxygen isotope method: analysis of the 18O/16O ratio in marine sediments and ice Thermoluminescence (TL): determination of the time elapsed since the material containing crystalline minerals was exposed to sunlight Varve chronology: counting and measuring thicknesses in annual paired layers of stratified limnic sediments (varved clays) Dendrochronology: tree-ring dating based on the analysis of patterns of tree-rings Pollen analysis: Reconstruction of vegetation analyzing the distribution of pollen grains of various species contained in deposits Lichenometry: geochronologic aging using lichen growth (Rhizocarpon geographicum) to determine the age of exposed rocks

5 III CLIMATE CHANGE Indication & Reconstruction

Archives Dating Methods

Loess-paleosol-sequence and chrono- stratigraphy of the Baoji loess profile in the Chinese Loess Plateau (GEBHARDT et al. 2007:301)

„L“ in the second column indicates (glacial) loess and correspond to glacial (even-numbered) marine isotope stages (left column)

„S“ indicates (interglacial) soil formation and corresponds to interglacial uneven- numbered isotope stages (right column)

The correlation allows a back dating by means of remanent magnetization (right column) 6 III CLIMATE CHANGE Causes

External and Internal Forcing Overview

Natural causes of climate changes 1. Changes of Earth-Sun relationships (i.e. the Earths’ orbital parameters) and changes of solar radiation emission (cyclic fluctuations of solar activity) 2. Changes of the surface structure and the planetary albedo of the Earth (depending on land-sea-distri- bution, topography, ice cover, cloud cover) 3. Changes of the chemical compo- sition of the Earths’ atmosphere (carbon dioxid, water vapor content, methane etc.) or the amount of aerosols 7 III CLIMATE CHANGE Causes

Orbital and Solar Variations Earth-Sun-Relations

8 III CLIMATE CHANGE Causes

Orbital and Solar Variations Earth-Sun-Relations

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Orbital and Solar Variations Milankovitch-Cycles

Precession

19.000, 22.000 and 24.000 Years

Obliquity

41.000 Years

Eccentricity 95.000, 125.000 and 400.000 Years

10 III CLIMATE CHANGE Causes

Orbital and Solar Variations Milankovitch-Cycles

Now [ka ago]

Milutin Milanković (1879 – 1958)

James Croll (1864)

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Orbital and Solar Variations Sunspot Numbers

Prior to 1749, sporadic observations of sunspots were compiled and placed on consistent monthly framework by HOYT & SCHATTEN (1998). Since ~1749, continuous monthly averages of sunspot activity were reported by the Solar Influences Data Analysis Center, World Data Center for the Sunspot Index, at the Royal Observatory of Belgium. The ~11 year solar magnetic cycle is associated with the natural waxing and waning of solar activity. 12 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

North American Plate

Eurasian Plate

African Pacific Plate Plate South American Indo-Australian Plate Plate

250 Mio. yrs. b.p. | 200 Mio. yrs.Antarctic b.p. | 150 Plate Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now

13 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 14 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 15 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 16 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 17 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 18 III CLIMATE CHANGE Causes

Surface Structure of the Earth Land-Sea-Distribution

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 19 III CLIMATE CHANGE Causes

Surface Structure of the Earth Orogenesis and Orography

250 Mio. yrs. b.p. | 200 Mio. yrs. b.p. | 150 Mio. yrs. b.p. | 100 Mio. yrs. b.p. | 50 Mio. yrs. b.p. | Now 20 III CLIMATE CHANGE Causes

Surface Structure of the Earth Orogenesis and Orography

OROGENESIS

Physical Atmosphere Weathering

Chemical Biosphere Weathering Pedosphere

Translocation Hydrosphere and Deposition

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Surface Structure of the Earth Thermohaline Circulation

Salinity [PSS]

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Surface Structure of the Earth Orogenesis and Orography

23 III CLIMATE CHANGE Causes

Chemical Composition of the Atmosphere Volcanism

North American Plate Eurasian Plate

African Plate Pacific Plate South American Plate Indo-Australian Plate

Antarctic Plate

Distribution of active volcanoes in the Holocene with a significant concentration at plate margins and subduction zones (GEBHARDT et al. 2007: 269) 24 III CLIMATE CHANGE Causes

Chemical Composition of the Atmosphere Volcanism Volcanism Solid and/or gaseous components are raised by volcanic activities. The types of eruption differentiate between: • Exhalation: Outgassing • Effusion: Non-explosive delivery of solid and liquid components • Explosion: Ejection of flowed and/or solid particles

25 III CLIMATE CHANGE Causes

Chemical Composition of the Atmosphere Volcanism

The June 12, 1991 eruption column from Mount Pinatubo taken from the east side of Clark Air Base (USGS 2010)

26 III CLIMATE CHANGE Climate History

Evolution of Climate Geological Time Table 2,59 248 542

27 (www.geo.cornell.edu/eas/education) 28

2,59 Climate History 5 % 21 % (www.ozh2o.com) Evolution of the Earth’s Atmosphere Evolution of the Earth’s 20 % % 5 % 1 % 0.04 0.0001 %

248 5 %1 % 60 % % 3 10 % 60 % % 5 65 % % 0-4 78 % 35 %35 % % 1 21 % 10 % Key phases in the development of atmosphere in phases Key Hydrogen Water Vapour Vapour Water Nitrogen Carbon Dioxide Helium Ammonia Methane / Sulphur Dioxide Oxygen Time [Bil. yrs b.p.] [Bil. yrs Time - 4,5 4,0 4,0 - 3,5 3,5 - 2,1 2,1 - 1,5 1,5 - 0,8 Atmosphere First Second Third Fourth Modern 542 III CLIMATE CHANGE III CLIMATE Evolution of Climate III CLIMATE CHANGE Climate History

Evolution of Climate Precambrian

Climate simulation for a „Snowball Earth-Situation“ before 700 Mio. yrs b.p. 29 III CLIMATE CHANGE Climate History

Evolution of Climate Precambrian

Global paleogeography for late proterozoic (600 Mio. yrs b.p.) 30 III CLIMATE CHANGE Climate History

Evolution of Climate Paleozoic and Mesozoic

warmer next figure

Ice Age

Ice Age

colder Mio. yrs b.p. cambrian ordovician silurian devonian carboniferous permian triassic jurassic cretaceous tertiary quat. PALEOZOIC MESOZOIC CENOZOIC Global changes in temperature of the last 542 Mio. years – deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

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Evolution of Climate Paleozoic and Mesozoic

warmer next figure

Ice Age

Ice Age

colder Mio. yrs b.p. cambrian ordovician silurian devonian carboniferous permian triassic jurassic cretaceous tertiary quat. PALEOZOIC MESOZOIC CENOZOIC Global changes in temperature of the last 542 Mio. years – deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

Late Permian Paleogeography of the Earth (http://jan.ucc.nau.edu)

32 III CLIMATE CHANGE Climate History

Evolution of Climate Tertiary

-+12[°C] next figure -+9

-+6

-+3

--3

--6

--9

--12[°C] Mio. yrs b.p. paleocene eocene oligocene miocene plioc. pl. PALEOGENE NEOGENE Global changes in temperature of the last 65 Mio. years – deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

33 III CLIMATE CHANGE Climate History

Evolution of Climate Late Tertiary and Quaternary

next -+4[°C] figure

-+2

--2

--4

--6

--8

Mio. yrs pliocene pleistocene NEOGENE Global changes in temperature of the last 5,3 Mio. years - deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

34 III CLIMATE CHANGE Climate History

Evolution of Climate Late Quaternary

Mindel-Riss interglacial Riss-Würm interglacial next -+4[°C] figure

-+2

--2

--4

--6

--8 Mindel glacial Riss glacial Würm glacial kyr pleistocene NEOGENE

Changes in temperature in the Artic of the last 420.000 years – deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

35 III CLIMATE CHANGE Climate History

Evolution of Climate Late Pleistocene and Holocene

-0[°C] Dansgaard-Oeschger-Events --2

--4

--6

--8

Younger Dryas --10 kyr pleistocene holocene NEOGENE

Changes in temperature in Greenland (ice cores) of the last 50.000 – deviations from the contemporary mean temperature (BUBENZER & RADTKE 2009)

36 III CLIMATE CHANGE Climate History Evolution of Climate Combined variation of excentricity, obliquity and precession

MIS: Marine Isotope Stage

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Source: Gebhard et al. 2011 III CLIMATE CHANGE Climate History

Evolution of Climate Foraminifera indicating climate change Neogloboquadrina pachyderma: relative abundance vs. sea surface temperature

https://www.ngdc.noaa.gov/mgg/geology/hh1996/pachy.html http://www.scielo.cl/fbpe/img/rchnat/v73n2/img10.jpg Bulk oxygen isotopic composition (d18O) of carbonate depends on the water temperature prevailing during its precipitation. 38 III CLIMATE CHANGE Climate History

Evolution of Climate Exemplary time series of paleoclimate data

DSDP: Deep Sea Drilling Project

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Evolution of Climate Ice-rafting deposition (IRD) in the Atlantic

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Evolution of Climate Holocene

Non-Tree Pollen

Shrub Pollen

Tree Pollen

cal. 14C-data [yr bp]

Local Pollen Zone

Chronozones

Lithostratigraphy

Profile Depth [cm] Pollen-Diagram ‘Schurtenseekar’ (Black Forest, 830m NN) PB = Preboreal, BO = Boreal, AT = Atlanticum, SB = Subboreal, SA = Subatlanticum (GEBHARDT et al. 2007)

41 III CLIMATE CHANGE Climate History

Glaciation of the Last Glacial Maximum

?

Ice age Weichsel/Würm about 20.000 years ago (BUBENZER & RADTKE 2009) 42 III CLIMATE CHANGE Climate History

Glaciation of the Last Glacial Maximum

?

Ice age Weichsel/Würm about 20.000 years ago (BUBENZER & RADTKE 2009) 43 III CLIMATE CHANGE Climate History

Evolution of Climate Holocene

T[°C] OH = Holocene Optimum

10.000 Years OJ = Medieval Optimum

PJ = Little Ice Age

OK = Modern Optimum

1.000 Years = Stein des Anstoßes

Time b.p. [yr]

Changes of averaged air temperatures in the northern hemisphere in the last 10.000 years (GEBHARDT et al. 2007: 250) 44 III CLIMATE CHANGE Climate History

Evolution of Climate Holocene

T[°C] OH = Holocene Optimum

10.000 Years OJ = Medieval Optimum

PJ = Little Ice Age

OK = Modern Optimum

1.000 Years = Stein des ? Anstoßes

Time b.p. [yr]

Changes of averaged air temperatures in the nothern hemisphere in the last 10.000 years (GEBHARDT et al. 2007: 250) 45 III CLIMATE CHANGE Climate History

Evolution of Climate Historical Climatic Fluctuations

T[°C] OH = Holozänes Optimum

OJ = Mittelalterliches Optimum

PJ = Kleine Eiszeit

OK = Modernes Optimum

= Stein des ? Anstoßes

Anomalies of air temperature in the northern hemisphere in the last 1000 years – deviations from the mean value of the Climate period 1961-1990 (IPCC 2001) 46 III CLIMATE CHANGE Climate History

Evolution of Climate Historical Climatic Fluctuations

T[°C] OH = Holozänes Optimum

OJ = Mittelalterliches Optimum

PJ = Kleine Eiszeit

OK = Modernes Optimum

= Stein des ? Anstoßes

Anomalies of air temperature in the northern hemisphere in the last 1000 years – deviations from the mean value of the climate period 1961-1990 (IPCC 2007) 47 III CLIMATE CHANGE Recent Climate Change

Period of Instrumental Observation Trends of Temperature

Trend-Analyses: 1856-2000: +0,6°C (0,004°C/yr) 1901-2000: +0,7°C (0,007°C/yr) 1981-2000: +0,3°C (0,017°C/yr) Temperature-Anomalies [°C] Temperature-Anomalies

Anomalies and trends of global air temperature (1856–2004) – deviations from the reference period 1961-1990 (JONES et al. 2005) 48 III CLIMATE CHANGE Recent Climate Change

Period of Instrumental Observation Findings of the AR4 (IPCC 2007)

Cold days, cold nights, and frost events have become less frequent. Hot days, hot nights, and heat waves have become more frequent. Trend-Analyses: Eleven of the twelve years in the period (1995–2006) rank among the top 12 warmest years 1856-2000: +0,6°C (0,004°C/yr) in the instrumental record (since 1850, towards the end of the Little Ice Age). 1901-2000: +0,7°C (0,007°C/yr) Warming in the last 100 years has caused about a 0.74 °C increase in global average 1981-2000: +0,3°C (0,017°C/yr) temperature.

Average Arctic temperatures increased at almost twice the global average rate in the past 100 years.

It is likely that greenhouse gases would have caused more warming than we have observed if not for [°C] Temperature-Anomalies the cooling effects of volcanic and human-caused aerosols. See global dimming.

Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1300 years (including both the Medieval Warm Period and the Little Ice Age). Anomalies and trends of global air temperature (1856–2004) – deviations from the reference period 1961-1990 (JONES et al. 2005) 49 III CLIMATE CHANGE Recent Climate Change

Period of Instrumental Observation Trends of Temperature

Trend-Analyses: 1856-2000: +0,6°C (0,004°C/yr) 1901-2000: +0,7°C (0,007°C/yr) 1981-2000: +0,3°C (0,017°C/yr) Temperature-Anomalies [°C] Temperature-Anomalies

AnomaliesObserved linear and trends trends of of ground global level air temperature air temperature (1856–2004) in the period – 1891 deviations to 1990 from – global the referencemap in 5° Lat./Long. period 1961-1990 resolution (JONES (JONES et et al. al. 2005) 2005) 50 III CLIMATE CHANGE Recent Climate Change

Observed changes in annual average surface temperature

Source: IPCC 2013, WG1 51 III CLIMATE CHANGE Recent Climate Change

Period of Instrumental Observation Trends of Precipitation

Precipitation trends in the period from 1900 to 1999 – right hand scale shows latitudinal averages of land surface areas (IPCC 2001) 52 III CLIMATE CHANGE Recent Climate Change

Observed changes in annual average precipitation

Source: IPCC 2013, WG1

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