Mikkelsen A., Langhelle O. (eds.) Arctic Oil and Gas. Sustanability at Risk?

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Disease and death from heat waves, floods and drought will increase. The report

also predicts that 30 per cent of species will be at risk of extinction by 2050. Even

if greenhouse gas emissions are immediately reduced, changes are inevitable.

Humans will have to adapt to survive.

It is not only about future impacts. The World Health Organization (WHO) esti-

mates that climate change is already causing at least 150,000 excess deaths per year.

One major killer is malaria: warmer average temperatures allow the mosquito that

transmits malaria to spread into the highlands. Ongoing effects of global warming

vary greatly from one region to the next, with perhaps the most striking example

being shifting precipitation. There has been a 20 per cent decline in snowmelt in the

United States Pacific Northwest in the last 50 years as the region has warmed. An

increase in dryness has started and will accelerate in the Caribbean Region as well

as all around the Mediterranean. An increasing wetness at high latitudes will also

occur in the Northern hemisphere. Here an increase of 1–3∞C is beneficial for the

major cereals, whereas in the low latitudes even a 1∞C increase results in an almost

immediate decrease in yield. A more than 3∞C warming is detrimental to growth

also at high latitudes. According to climate models, a 3∞C increase is possible in this

century if CO

emissions continue at present rates.

More local warming impacts are the melting of glaciers around the globe.

Several snow-covered peaks have already disappeared in the last 50 years. As

more glaciers melt in places like the Himalayas and the Andes, spring and

summer melt will become history. Water storage in the form of snow and ice will

disappear with grave consequences for irrigation and domestic potable water

supply. Sea-level rise from melting glaciers will flood low-lying coastal areas all

around the globe. Heat waves experienced in Europe in 2003, where perhaps

30,000 people died, will in the next few years become ever more extreme,

frequent and deadly for people, flora and fauna. Widespread mortality and

bleaching of corals already living near their upper limits of temperatures, have

already become an uncomfortable certainty.

No one region of the globe seems exempt. Although the WGII report empha-

sizes that not everyone will bear the consequences equally, the global net damage

costs resulting from a climate change will become significant. Some people will

be exposed to severe climate change, some will be more sensitive and some will

be less able to adapt to changes. People living in low-latitude countries where

drying will predominate, have economies based largely on agriculture and are

already today sensitive to droughts. Adaptation to climate change is simply a

matter of survival. It is not enough to stem the greenhouse gas emissions, as the

current level is already enough to sustain a temperature increase for another

hundred years. The UN’s Millennium Development Goals, ensuring environmen-

tal sustainability, will not now be met as a result of climate change.

A changing Arctic

The edges of Greenland are losing ice at an alarming rate, faster and faster

compared to the ever-updated estimates. The IPCC (2007) findings suggest an

46 Torleiv Bilstad

Climate change and consequences for the Arctic 47

underestimation of CO

importance and that the future loss of Arctic sea ice may

be more rapid and extensive then predicted. Likewise, sea-level rise may be

responding even more quickly than climate models indicate.

Climate change and global warming are considered major environmental and

economic threats to the global community. Commitments to prevent and mini-

mize its causes and to mitigate adverse effects are a priority on the political and

scientific agendas. Strategies are implemented to achieve reductions in CO

which is considered to be the major human-induced greenhouse gas (GHG). The

atmospheric CO

concentration of 385 parts per million (ppm) is the highest it has

been in 10 million years (Corell, 2006). The Kyoto Protocol is a driving force in

negotiations for ambitious reduction targets for GHG. Even if these commitments

were fully implemented, however, significant changes in climatic conditions will

occur throughout the twenty-first century.

The Arctic is rich in hydrocarbons (HCs) and production of oil and gas will

improve the global energy security. However, burning of HCs, irrespective of

where they are mined, advances global warming. Models suggest that, over the

next century, our planet will get warmer to the tune of 1.4–5.8∞C on average,

depending on the levels of GHG emissions. Changes in climate influence snow

and ice as well as the way of life in the Arctic. Human adaptation, therefore,

becomes a necessity.

The Arctic is generally characterized as hostile and cold. However, maritime

and continental influences contribute in shaping significant climate variables

with unpredictable weather for the region. At high latitudes, the solar radiation

is low or completely absent in the winter, contrasting with high levels during

long summer days. The low elevation of the sun above the horizon during the

Arctic winter makes even small topographic features significant in shaping local

differences in microclimate due to shading. The high albedo owing to snow and

ice reduces the absorption of solar energy. As a consequence, the heat gained

during long summer days is small and highly dependent on surface properties.

The Arctic is highly vulnerable to effects of global warming as solid snow and

ice, including tundra, undergoes a phase shift to liquid water at temperatures

above 0∞C.

In Russia, Canada and Alaska, subsistence activities of the native populations

are directly or indirectly threatened by the oil and gas industry. The direct

effects are connected to the pollution of fragile land and water, as well as

construction and operation of infrastructure for oil and gas developments that

deflect animals from traditional migration routes and make access for hunters

difficult. The indirect effects are related to emissions and pollution from the

burning of fossils for energy production anywhere, with CO

interfering with

natural climate variations. The transportation of chemicals by air and sea

from industrial nations to the Arctic also affects the nutrition chain through

bioaccumulation, which is very destructive to societies relying on a subsistence

lifestyle. Climate change also threatens traditional knowledge of ice and wildlife

among native peoples. Biodiversity and sustainability of the environment are

at risk.

48 Torleiv Bilstad

Science behind the greenhouse phenomenon

The text ‘Global Warming, the Complete Briefing’ (Houghton, 2004) covers rele-

vant research reviewed in this paragraph. Jean-Baptiste Fourier first recognized

the warming effect of the greenhouse gases, CO

and water vapour, in 1827. He

pointed to the similarity between what happens in the atmosphere and under the

glass of a greenhouse, i.e. the ‘greenhouse effect’. Around 1860, John Tyndall

measured the absorption of infrared radiation by CO

and water vapour. He also

suggested that a cause of the Ice Ages might have been a decrease in the green-

house gas CO

in the atmosphere. Svante Arrhenius in 1896 calculated the effect

of an increasing concentration of greenhouse gases. A doubling of the CO

concentration will increase the average global temperature by 5–6∞C. This esti-

mate is still valid a century later. G. S. Callendar in 1940 was the first to calcu-

late the warming due to increasing CO

from burning of fossil fuels.

The first expression of concern about an impending climate change was in

1957 when Revelle and Suess at the Scripps Institute of Oceanography published

a paper pointing to a build-up of CO

in the atmosphere (Houghton, 2004).

Routine measurements of in 1896 from the observatory on Mauna Kea in Hawaii

commenced. The rapid increasing use of fossil fuels since 1957 has led to the

topic of global warming through a large-scale geophysical experiment. The

natural greenhouse effect is due to methane (CH

), water vapour, CO

and nitrous

oxide (N

O). The amount of water vapour in the atmosphere depends mostly

on air temperature at the ocean surface with associated evaporation from

the oceans. Carbon dioxide is different, however: the level has increased by

30 per cent since the Industrial Revolution owing to the burning of fossil fuels,

and the removal of forests and plants. In the absence of such controlling factors,

the rate of increase in atmospheric CO

will accelerate and double in the next

hundred years (Houghton, 2004).

The global carbon balance

The carbon content of the Earth’s atmosphere has increased from 360 Gt mainly

as CO

at the last glacial maximum to 560 Gt during pre-industrial times to 730 Gt

today (Zimov, Scuur and Chapiin, 2006). These changes reflect redistributions

among the main global carbon reservoirs. The largest such reservoir is the ocean,

which contains 40,000Gt, including 2500 Gt organic carbons, followed by soils

at 1500 Gt and vegetation at 650Gt. There is also a large geological reservoir

from which 6.5Gt carbons are released annually by burning fossil fuels.

Permafrost is an additional large carbon reservoir that is rarely incorporated

into analyses of changes in global carbon reservoirs. During the glacial age,

frozen loess, windblown dust or yedoma in Siberia, was deposited to an average

depth of 25 m covering more than 1 million km

in northern Siberia and Alaska.

These frozen soils have an average carbon content of 10–30 times that found in

deep non-permafrost mineral soils. The carbon reservoir from yedoma is 500 Gt,

plus other permafrost soils at 450 Gt. An additional reservoir is included in peat

Climate change and consequences for the Arctic 49

lands of Western Siberia, which is estimated at 70Gt of carbon. Considering that

the carbon content in the atmosphere is 730 Gt today, the potential release from

permafrost could become devastating.

How fast will it thaw? Organic matter in yedoma decomposes quickly when

thawed, up to 40 g carbon/m

/day (Zimov, Scuur and Chapiin, 2006). Field obser-

vations suggest that these rates are sustained and that carbon in yedoma will be

released within a century; a striking contrast to the preservation of carbon for tens

of thousands of years when frozen in permafrost. Permafrost is defined as

bedrock, organic or earth material that has temperatures below freezing persist-

ing over more than two consecutive years. The impact of permafrost thaw on both

climate and socio-economic conditions is already serious. The southern border

for permafrost has been migrating northward by hundreds of miles over the last

couple of decades. Figure 3.1 (Arctic Climate Impact Assessment; ACIA, 2004)

shows a rapid decrease in the ice roads necessary for travel on the North Slope

of Alaska.

Tundra lakes are net emitters of methane when thawing. Methane is 23 times

as effective as a greenhouse gas compared to carbon dioxide. Fluctuations of CO

and CH

in the atmosphere over the past 400,000 years are depicted in Figure 3.2

(Petit, Jouzel, Raynaud et al., 1999). In Siberia, previously frozen tundra lakes are

emitting and bubbling CH

as the greenhouse gas is released due to natural degra-

dation of carbon-organics under anoxic conditions and increasing temperature.

(Days)

Alaska Winter Tundra Travel Days

(1970–2002)

250

200

150

100

1970 1975

1980 1985 1990 1995 2000

Figure 3.1 Maximum oil exploration travel activities on the tundra (ACIA, 2004).

Preservation of carbon in permafrost has lasted for tens of thousands of years, but

the lakes are rapidly disappearing now, as the melting process continues.

Ice is important. We are, however, losing it and, therefore, also losing impor-

tant archives informing us about past climates. The relationship between green-

house gas levels and temperatures, evident in data from ice cores, illuminates

climates in the geological past, and may be a useful guide to the future (Kennedy

and Hanson, 2006). Fifty million years ago CO

levels may have topped

1000 ppm with sea levels 50 m higher than today. CO

gradually decreased as

marine organisms fixed carbon through photosynthesis and then buried it by sink-

ing into the ocean basins. This CO

reduction and a corresponding decrease in

temperature allowed ice sheets to develop in Antarctica starting 30–40 million

years ago. By 3–4 million years ago, CO

levels probably dropped to or below the

pre-industrial level of about 290ppm and permanent ice sheets appeared in the

Northern Hemisphere. As subsequent glaciations came and went, CO

concentra-

tion and temperature were tightly linked. When both decreased, ice sheets grew

and sea levels were lowered by more than 100 m below today’s level. When both

went up, there were relatively stable periods with high sea levels. A central feature

of this baseline is that at no time in at least the past 10 million years have CO

levels in the atmosphere exceeded 385 ppm, the 2007 level.

Polar warming

Polar warming is happening now: the Arctic ice is melting. By looking back, we

may predict the Earth’s climate future. The Pliocene epoch 3–4 million years ago

50 Torleiv Bilstad

1600

1400

1200

1000

Methane (ppbv)

800

600

400

400,000 350,000 300,000 250,000 200,000

Methane

Carbon dioxide

Age (Years before present)

Greenhouse Gas Record from the Vostok Ice Core

now about

385 ppmv

150,000 100,000 50,000 0

180

210

240

Carbon dioxide (ppmv)

270

300

330

360

Figure 3.2 Methane concentration doubling over the last 150 years (Petit, Jouzel, Raynaud

et al., 1999).

Climate change and consequences for the Arctic 51

experienced 3∞C warmer air than today, with a similar CO

content in the atmos-

phere (Fedorov, Dekens, McCarthy et al., 2006). Sea levels, however, were 25m

higher. Humans, therefore, may already have put the world on a path back to

that epoch. The accelerating decay of ice sheets in Greenland and Antarctica,

coupled to concurrent rise in CO

concentrations, suggest that we should expect

other changes as well. The significant warming observed in the Arctic regions

from 1920 to 1940 and the subsequent cooling from 1940 to 1960 was natural

climate variability. The present warming, also largest in the Arctic, is primarily

caused by human activities through increasing release of greenhouse gases to the

atmosphere.

Air temperatures over the continent of Antarctica have risen three times faster

than the rest of the world over the past 30 years (Turner, Lachlan-Cope, Colwell

et al., 2006). By analysing historical data from high-altitude weather balloons, it

was concluded that temperatures in the lower 9km of the atmosphere above

Antarctica have risen by more than 2∞C since the early 1970s. This is the largest

regional warming on Earth at this level. Scientists are keen to understand the

change in temperatures over the continent as the region holds enough water in its

ice to raise sea levels by 57 m. Temperature rises on parts of the surface of

Antarctica have been seen for some time. The western side of the Antarctic

Peninsula is known to have the largest annual warming seen anywhere in the

world with increases of over 2.5∞C in the last 50 years. Such new findings about

Antarctic warming are particularly important because, until now, researchers had

only partial – and often conflicting – temperature readings from a few surface

stations on the icy continent. The finding opens many new research questions for

polar climate scientists. The rapid surface warming of the Antarctic Peninsula and

the enhanced global warming signal over the whole continent show the complexity

of climate change. If greenhouse gases are having an even greater impact in

Antarctica than across the rest of the world, the question is why?

The findings from the award-winning Climate and Environment Changes in

the Arctic (CECA) project (Nansen Centre, 2005) indicate large potential climate-

change consequences of both a positive and negative nature affecting fisheries, oil

and gas activities, transport through the Northern Sea Route, ocean circulation,

including the North Atlantic Current, and climate in Europe and the Arctic. The

ice cover in the Arctic regions has decreased by 3 per cent per decade since 1978.

The thicker multi-year ice has been reduced by 7 per cent per decade, which

indicates that the Arctic sea-ice cover may be in for major transformation

(Figure 3.3). A doubling of the atmospheric CO

is expected within a hundred

years. Simulations by climate models show that the ice could disappear during the

summer months. During the winter months the reduction may be about 20 per cent,

with the Barents Sea being open all year around.

The increase of greenhouse gases will influence the low-pressure systems

between Greenland and Iceland. They will increase in strength and lead to a

warmer, wetter and wilder climate in Northern Europe. Bindschadler (2006) shows

accelerated sea-level rise and increasing frequency of glacial earthquakes as a

result of rapid climate change in the polar regions. Owing to a large temperature

contrast between the warm ocean water and the cold ice, melting occurs at a very

rapid rate. The melting reduces the friction that slows the advances of these

glaciers, allowing them to accelerate.

Ekstrom, Nettles and Tsai (2006) also recorded a significant and unexpected

increase in the number of glacial earthquakes. Glaciers are thought of as ‘inert’and

slow moving, but in fact they can also move rather quickly. Some of Greenland’s

glaciers are as large as Manhattan and may move 10 m in less than a minute, a jolt

that is sufficient to generate moderate seismic waves. This increase in the glaciers’

rates of flow offer additional potential evidence of global warming.

How fast will the ice sheets of Greenland and Antarctica disappear? How fast

and how far will there be a rise in sea level? At the moment, ice loss from

Greenland and West Antarctica combined is contributing less than half of the

ongoing 2 mm/year rise in sea level. The rest comes from melting mountain

glaciers around the globe and the simple thermal expansion of sea water (Kerr,

2006a). Climate model simulations are integrated into ice-sheet models and

paleo-climate data to show that the northern latitudes, particularly the Arctic,

were significantly warmer during the last inter-glaciations with sea level several

metres higher than at present. Models estimate that the Greenland Ice Sheet

contributed between 2.2 and 3.4 m of sea-level rise in the penultimate deglacia-

tions. Models predict that surface temperatures will be as high by year 2100 as

they were 130,000 years ago; between the last two Ice Ages. The mass of ice

decreased by 152 ± 80km

from 2002 to 2005, mostly from the West Antarctic Ice

Sheet. The loss of mass from Greenland doubled in the last 10 years (Kerr, 2006a).

Ice loss around the margins of the island is proceeding faster than at the centre.

52 Torleiv Bilstad

August Ice Extent

8.5

7.5

Extent (million km

)

6.5

5.5

1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

2007

5.32 million km

2006 2008

Year

National Snow and Ice Data Center

Figure 3.3 Arctic ice cover (Norsk Romsenter/National Snow and Ice Center, 2007).

Large and sudden sliding of glaciers triggers glacial earthquakes. Around

Greenland the annual number of glacial earthquakes has doubled since 2002, as

verified by satellite and airborne radar and laser altimeter measurements.

The Greenland ice sheet is 1,700,000 km

in area and up to 3 km thick and would,

if melted completely, raise global sea level by 7m. The velocity of several large

glaciers draining the ice sheet to the sea has recently doubled to reach a level of

more than 12 km/year. This implies that current estimates of global sea-level rise of

about 0.5 (± 0.4) m before 2100 may be too low. Figure 3.4 shows the Northern

Hemisphere surface air temperature and CO

as measured from ice-core samples.

A compilation of temperature records (Osborn and Briffa, 2006) shows that the

geographic extent of recent warmth is greater than the notable Medieval Warm

Period of the years 890–1170. The last 100 years are more striking than either the

Medieval Warm Period or Little Ice Age. It is a period of widespread warmth

affecting nearly all the records analysed from the same time. These observations

add more convincing evidence of the impacts of increasing greenhouse gas emis-

sions. As such, the findings support evidence pointing to unprecedented recent

climate warming linked with human activity. The Earth in 2006 was absorbing

0.85 ± 0.15 W/m

more energy from the sun than it is re-emitting to space. This

imbalance is confirmed by precise measurements of increasing ocean-accumulated

heat over the past 10 years. Theoretically this should lead to an additional global

warming of about 0.6∞C without further change in atmospheric composition

(Turner, Lachlan-Cope, Colwell et al., 2006).

Climate change and consequences for the Arctic 53

−420

−440

−460

δD (%)

−480

400,000 300,000 200,000 100,000

Vostok: Temperature

Vostok: CO

180

210

240

270

300

330

levels now 25% above the

previous maximum of ~300

ppmv about 325,000 years ago

360

390

ppmv CO

Now

Years before Present

Figure 3.4 Concentrations of CO

and temperature from 400,000 years Vostok Ice Core

data set (Corell, 2006).

Open ocean – warm ocean water from the tropics

Oceans contain 97 per cent of the Earth’s water and, therefore, are fundamental in the

global hydrological cycle. Water evaporation from the oceans averages 86 per cent

of the total annual evaporation and, as such, is central in planetary energy

exchanges. Oceans receive 78 per cent of global precipitation. As an example of

the magnitude of this number, a 1 per cent change in the precipitation of the

Atlantic equals the annual runoff to the Mississippi River (Kerr, 2006b).

The oceans control the timing and magnitude of changes in the global climate

system by acting as a heat sink. Summertime Arctic Ocean ice may soon disap-

pear. Its melting, however, does nothing to increase the volume of ocean water:

the ice is already floating in the ocean. The melt water from receding mountain

glaciers and ice caps, on the other hand, is certainly raising sea level. Nobody

prior to Roald Amundsen in 1906 had tackled the Northwest Passage, and

returned alive. It took Amundsen three years to make the journey. In 2006, the

transit is easily done in a couple of weeks in open Arctic waters, which in

Amundsen’s time were ice-clogged. Something has happened in a hundred years.

The heat-carrying ocean conveyor that warms the far northern Atlantic is over-

heating. If the greenhouse disturbs this conveyor, it means trouble (Kerr, 2006b).

A major warming of the Antarctic winter troposphere, larger than any previ-

ously identified regional troposphere warming on Earth, came to light by quality-

controlled Antarctic radiosonde observations. The data show that regional

mid-troposphere temperatures have increased at a statistically significant rate of

0.5–0.7∞C per decade over the past 30 years (Turner, Lachlan-Cope, Colwell et al.,

2006). There is also evidence that warmer subsurface waters are reaching the

Earth’s polar latitudes. Moreover, it indicates that the ocean plays a more critical

role than the atmosphere in determining near-term glaciological contributions to

change in sea level.

The tropical and mid-latitude oceans have been warming in recent decades.

Heat has been transported below the surface, even below 1000 m in the North

Atlantic, where deep convection carried increased heat to greater depths. The

warmest water in the polar oceans is neither at the surface nor at the bottom. In

the Amundsen Sea, the warmest water is concentrated at a depth of 600 m. The

recent glacier acceleration could be due to warmer intermediate-depth water

that can access the deep grounding lines of glaciers, where the ice first floats

free from the bed. These glaciers flow out to the ocean in deep channels – floating

ice shelves a few hundred metres thick. Sea-level rise from melting of these polar

ice sheets is one of the largest potential threats of future climate change. Both the

Greenland Ice Sheet and Antarctica may be vulnerable. The record of past ice-

sheet melting indicates that the rate of future melting and related sea-level rise

could be faster than widely thought.

Glaciers and ice streams periodically lurch forward with sufficient force to

generate emissions of elastic waves that are recorded on seismometers world-

wide. Such glacial earthquakes on Greenland show a strong seasonality as well as

doubling of their rate of occurrence over the past five years. These temporal

54 Torleiv Bilstad

patterns suggest a link to the hydrological cycle and are indicative of a dynamic

glacial response to changing climate conditions (Ekstrom, Nettles and Tsai et al.,

2006).

Concluding remarks

At no time in at least the past 10 million years has the atmospheric CO

concen-

tration exceeded the present value of 385 ppm. In Alaska and western Canada, the

average winter temperatures have increased by as much as 3–4∞C over the past

60 years. The global average increase over the past 100 years has been 0.6 (± 0.2)∞C.

Glaciers are disappearing and we are losing unique archives of the Earth’s

climate history. The twentieth-century warming is apparent in the Arctic ice cores

as well as in the low-latitude, high-altitude ice cores. The loss of low-latitude

glaciers threatens the water resources in many parts of the world. These ‘water

towers of the world’ affect nearly half of the world’s population in Asia, Africa

and South America. Glaciers are our most visible evidence of global warming.

They integrate many climate variables in the Earth’s system.

Changes in absorption of heat by the ocean as the ice disappears means a

switch from 85 per cent reflected (albedo) to 85 per cent absorbed. Population

growth is the main driver for climate change. The never-ending search for energy

results in burning of fossils and forests at an accelerating rate adding greenhouse

gases to the atmosphere.

Increasing effort is required in order to develop new energy technologies,

currently far from the market. Governments must play a greater role in stimulat-

ing this process, by investing in research and development. The world needs a

new global ‘Apollo’ project. This would stimulate education and enrolment at

universities in science and technology.

References

Arctic Climate Impact Assessment (ACIA 2004) Impacts of a Warmer Arctic: Arctic

Climate Impact Assessment, Cambridge: Cambridge University Press.

Bindschadler, R. (2006) ‘Hitting the ice sheets where it hurts’, Science, 311 (March 24): 1720.

Corell, R. (2006) Presentation at Transatlantic Symposium, June 15. Environmental and

Energy Study Institute. Online. Available HTTP: <www.eesi.org/briefings/2006/Energy

& Climate/6.15.06_ClimateSymposium>.

Ekstrom, G., Nettles, M. and Tsai, V.C. (2006) ‘Seasonal and increasing frequency of

Greenland glacial earthquakes’, Science, 311 (March 24): 1756.

Fedorov, A. V., Dekens, P. S., McCarthy, M., Ravelo, A.C., deMenocal, P.B., Barreiro, M.,

Pacanowski, R. C. and Philander, S. G. (2006) ‘The Pliocene paradox’, Science, 312

(June 9): 1485.

Houghton, J. (2004) Global Warming: The Complete Briefing, 3rd edition, Cambridge:

Cambridge University Press.

Intergovernmental Panel on Climate Change (IPCC, 2007). Online. Available HTTP:

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Kennedy, D. and Hanson, B. (2006) ‘Ice and history’, Science, 311 (March 24): 1673.

Climate change and consequences for the Arctic 55