Earth’s Climate System

Figure 10.1

Worldwide Average Preciptiation

Figure 10.2

Generalized Climate Regions

Figure 10.4

Tropical Climates (A)average T each month > 64 F (18 C)

Mesothermal Climates (C)   Average T of coldest month - 64-27F (18 - -3C)

Microthermal Climates (D)Warmest month > 50F (10C)Coldest month < 27F (-3C)

Polar Climates (E)No month > 50F (10C)

Dry, Arid, and Semiarid Climates (B)  (Evaporation > Precipitation)

Global Temperatures

Figure 10.28

Global mean surface temperatures have increased

The Land and Oceans have warmed

Carbon Dioxide Sources

Figure 10.29

Precipitation patterns have changed

Mother Earth -- Our Home

It is has water, oxygen and a hospitable climate

The following slides with this background are taken from the “Briefing on the IPCC Synthesis Report at COP-7”.

The El-Nino phenomena leads to floods and droughts throughout the

tropics and subtropics

El Niño years

La Niña years

The frequency, persistence and magnitude of El-Nino events have increased in the last 20 years

Sea Levels have risen

Weather-related economic damages have increased

Human activities have changed the composition of the atmosphere since the pre- industrial era

Examples include:

• non-polar glacier retreat

• reduction in Arctic sea ice extent and thickness in summer

• earlier flowering and longer growing and breeding season for plants and animals in the N.H.

• poleward and upward (altitudinal) migration of plants, birds, fish and insects; earlier spring migration and later departure of birds in the N.H.

• increased incidence of coral bleaching

Observed regional changes in temperature have been associated with observed changes in physical and

biological systems

Most of the observed warming in the past 50 years is attributable to human activities

Global mean surface temperature is projected to increase during the 21st century

Land areas are projected to warm more than the oceans with the greatest warming at high latitudes

Annual mean temperature change, 2071 to 2100 relative to 1990: Global Average in 2085 = 3.1oC

Some areas are projected to become wetter, others drier with an overall increase projected

Annual mean precipitation change: 2071 to 2100 Relative to 1990

Extreme Weather Events are Projected to Increase

• Higher maximum temperatures; more hot days and heatwaves over nearly all land areas (very likely)

• Higher minimum temperatures; fewer cold days frost days and cold spells over nearly all land areas (very likely)

• more intense precipitation events over many areas (very likely)

• increased summer drying over most mid-latitude continental interiors and associated risk of drought (likely)

• increase in tropical cyclone peak wind intensity, mean and peak precipitation intensities (likely)

• Increased mortality in old people in urban areas

• Damage to crops• Heat stress on livestock

• Extended range of pests and diseases

• Loss of some crop/fruit

• Land slides, mudslides, damage to property and increased insurance costs

• Reduced rangeland productivity, increased wildfires, decreased hydropower

• Damage to various ecological and socioeconomic systems

Projected changes during the 21st century

Examples of impacts

2020s

2050s

2080s

Initially increased agricultural productivity in some mid-latitude regions & reduction in the tropics and sub-

tropics even with warming of a few degrees

Branching coral Brain coral

coral bleaching events are expected to increase

Ecological systems have many interacting non-linear processes and are thus subject to abrupt changes and threshold effects arising from relatively small changes in driving variables, such as climate.

For example: Temperature increase beyond a threshold, which varies by crop and variety, can affect key development stages of some crops and result in severe losses in crop yields.

Mean sea level is projected to rise by 0.09 to 0.88m by

2100, but with significant regional variations

Increased risk of floods, potentially displacing tens of millions of people, due to sea level rise and heavy rainfall events,

especially in Small Island States and low-lying deltaic areas. Bangladesh is projected to lose about 17% of its land area with a sea level rise of one meter - very difficult to adapt due to lack of adaptive

capacity

projected

present

Developing countries are the most vulnerable to climate change

• Impacts are worse - already more flood and drought prone and a large share of the economy is in climate sensitive sectors

• Lower capacity to adapt because of a lack of financial, institutional and technological capacity and access to knowledge

• Climate change is likely to impact disproportionately upon the poorest countries and the poorest persons within countries, exacerbating inequities in health status and access to adequate food, clean water and other resources.

• Net market sector effects are expected to be negative in most developing countries

Adaptation has the potential to reduce adverse effects of climate change and can often produce immediate ancillary

benefits, but cannot prevent all damages

• Numerous adaptation options have been identified that can reduce adverse and enhance beneficial impacts of climate change, but will incur costs

• Greater and more rapid climate change would pose greater challenges for adaptation

Food production needs to double to meet the needs of an additional 3 billion people in the next 30 years

Climate change is projected to decrease agricultural productivity in the tropics and sub-tropics for almost any amount of warming

Wood fuel is the only source of fuel for one third of the world’s population

Wood demand will double in next 50 years

Climate change is projected to increase forest productivity, but forest management will become more difficult, due to an increase in pests and fires

Water Services

One third of the world’s population is now subject to water scarcity

Population facing water scarcity will more than double over the next 30 years

Climate change is projected to decrease water availability in many arid- and semi-arid regions

• Impact of warming and rising sea level on small islands

Con

tam

inat

ion

time

Climate change will exacerbate the loss of biodiversity

Estimated 10-15% of the world’s species could become extinct over the next 30 years

Biodiversity underlies all ecological goods and services

Food and Fiber Production

Provision of Clean and Sufficient Water

Maintenance of Biodiversity

Maintenance of Human Health

Storage and cycling of Carbon, Nitrogen, Phosphorus

Agricultural Lands

CoastalZones

ForestLands

FreshwaterSystems

Arid Lands & Grasslands

Climate change will affect the ability of ecological systems to provide a range of essential ecological goods and services

Cost of new technologies have declined steeply,but costs of conventional technologies have also

declined at a slower rate

Solar

Wind

Biomass

Natural gas Combined

Cycle

Advanced Coal

Pro

du

ctio

n c

ost

s (E

UR

O19

90/k

Wh

)

0.01

0.1

1

10

Cumulative Installed Capacity (MW)

100 10000 1000000

Electric technologies, EU 1980-1995, Source: IEA