1. GEOGRAPHY 310: URBAN CLIMATOLOGY

2. THE EARTH SYSTEM
ATMOSPHERE
HYDROSPHERE
CRYOSPHERE
GEOSPHERE
BIOSPHERE

3. THE CLIMATE SYSTEM

4. CLIMATE VERSUS WEATHER
Choose which one hurts less.

5. Weather: The condition of the atmosphere at any given time and place.
Climate: A description of average weather conditions.
Often, it is defined by statistical weather information such as average temperature or average total precipitation.

6. CLIMATE NORMAL

7. How Big Is Climate?

8. Temporal Aspects of Climate:
Climate Variability
Climate Change

10. LA Civic Center (USC Campus) Annual Mean Temperature (1878-2007)
Degrees F
Year
Data: NOAA NWS (Los Angeles/Oxnard)
Bill Patzert/JPL

11. CA Warming Due To:
• Land Use
• Greenhouse Gas
Warming
California
Temperature
Changes (°F)
331 Met. Stations

12. California’s Extreme Makeover

13. “How inappropriate to call this planet Earth when it is quite clearly Ocean.” – Arthur C. Clarke

14. WHAT CAUSES CLIMATE CHANGE?

16. Very well. Give the
heretic back his
research funding.
OK! I believe mankind
causes global
Warming!

17. Tide Gauge Observations
3.2 mm/year
2.0 mm/year
~ 8 inches
(20 cm)
0.8 mm/year
= 16,000 cubic miles!!!
Average Rate ~ 1.8 mm/year
(67,000 cubic km)
[Church and White, 2006]

18. The once-wide sand strip, swept away by waves and rising seas.
Sea Level Rise
Malibu’s “sandbagged” Broad Beach.
The once-wide sand strip, swept away by waves and rising seas.

19. To overturn the world economy based on the
musings of a few idiot leftist scientists is just
stupid, that’s what Global Warming is all about.
-Rush Limbaugh-

20. Typical Surface Weather Map

21. Climate change
Climate is defined as the statistical properties of the atmospheric variables like temperature, precipitation, and wind.
So, climate change can be defined as any change in some statistical property like mean temperature.

23. Human Transformation of the Land Surface
The current land surface little resembles what existed 100,000 years or even 3,000 years ago
Fire for ecosystem
management
Grazing
Deforestation
metal smelting
Agriculture
Urbanization

24. Global Land Cover Urbanization
Present
Urbanization
43% of Land Area
Dominated by Agriculture
% of Land Area
Built-up
3 - 6%
World Population
6.5 Billion

25. Current U.S. Urban Growth Rate is ~12.5%
Nearly 50% of the World’s Land Surface has been transformed by human action
80% of U.S. Population Lives in Urban areas
60%-80% of World’s Population in urban areas by 2025

26. Urban Areas and the Climate System

27. Can you find the Cities?
Why do cities appear this way in this thermal satellite image?

28. Net Primary Production (NPP)
Earth’s “Bio-Engine”
Net Primary Production (NPP)
NPP is the amount plant material produced on Earth.
It is the primary fuel for Earth’s food web.
Represents all available food and fiber.
NPP can be measured in terms of Carbon
(photosynthesis - CO2 exchange between atmosphere and biosphere (global climate change).
Land use strongly impacts NPP
Humans require almost 20% of Earth’s NPP capacity on land
NPP is the “Common Currency” for Climate Change, Ecological, & Economic Assessment.

29. Consequences of Urbanization on NPP-Carbon in the U.S.
NPP Lost or Gained (annual)
Due to Urbanization
Going from a pre-urban to a post urban world
Urbanization and NPP
NPP decreased 41.5 M tons C / year.
Roughly equivalent to the increase
created by 300 years of agricultural
development.
How can this happen when urban areas occupy only 3% of the land surface and agriculture occupies 29%?
Location, Location, Location.
Urbanization is taking place on the most fertile lands
Reduction of NPP may have biological significance:
Total Reduction
41.5 Mt C
From Ag Lands
25.5 Mt C
Annual loss of food web energy 400 Trillion kilocalories
(roughly equal to food energy requirement for 448 million people).
Reduction of actual food products equivalent to needs of 16.5 million persons annually
(about 6% of US population).
M. Imhoff/NASA