No Slide Title

Download Report

Transcript No Slide Title

CLIMATE AND
CLIMATE CHANGE
Jill F. Hasling, President
Certified Consulting Meteorologist
Weather Research Center
Houston, Texas
www.wxresearch.com
What is the ‘Greenhouse Effect’?
The Earth’s Greenhouse effect works by the
atmosphere facilitating convection . In other words,
the Earth’s ‘greenhouse effect’ works by modulating
radiation.
With out the ‘greenhouse effect’, the Earth would not
be habitable.
Without the ‘greenhouse effect’ the temperature of
the earth would be -18 deg C.
When you add the ‘greenhouse effect’ back in the
temperature is ~33 deg C.
What is Climate?
Climate is the average and variations of weather in a
region over long periods of time.
What is Climate?
Climate is determined by the long-term pattern of
temperatures and precipitation averages and
extremes at a location.
Climate descriptions can refer to areas that are local,
regional, or global.
Climate also describes different time intervals, such
as decades, years, seasons, months or specific dates
of the year.
What is Climate?
Climate is not the same thing as weather. Weather is
the minute by minute variable conditions of the
atmosphere on a local scale.
Climate is a conceptual description of an area’s
average weather conditions and the extend to which
those conditions vary over long time intervals.
What is Climate Change?
Climate change is a significant and
persistent change in the area’s
average climate conditions or their
extremes.
Climate has changed in the past, is
changing now and will change in the
future.
Types of Climates
• A --
TROPICAL CLIMATE
• B -- DRY CLIMATE
• C -- MOIST SUBTROPICAL MID-LATITUDE CLIMATE
• D -- MOIST CONTINENTAL MID-LATITUDE CLIMATE
• E -- POLAR CLIMATE
Types of Climates
•A
TROPICAL CLIMATE
• Climates in which the average temperature for all
months is greater than 64°F (18°C).
• Extend northward and southward from the equator to
about 15 to 25 degrees latitude.
• Example: Key West, FL
Types of Climates
•B DRY CLIMATE
• Arid and semi-arid deserts and steppes; evaporation
exceeds precipitation.
• Extends from 20 to 35 degrees latitude North and
South of the Equator.
• Example: Albuquerque, NM
Types of Climates
•C MOIST SUBTROPCIAL MID-LATITUDE CLIMATE
• Warm and humid summers (with frequent thunderstorms) and
mild winters. Warmest month is above 50°F (10°C). Coldest
month is above 32°F (0°C).
• Extends from 30 to 50 degrees latitude mainly on the eastern
and western borders of most continents.
• Example: Houston, TX
Types of Climates
•D MOIST CONTINENTAL MID-LATITUDE CLIMATE
• Warm to cool summers and cold winters. Warmest month is
above 50°F (10°C). Coldest month is below 32°F (0°C).
• Extends poleward from the moist subtropical mid-latitude
climate regions.
• Example: St. Paul, MN
Types of Climates
•E POLAR CLIMATE
• Cold temperatures all year with the warmest month
below 50°F (10°C).
• Found on the northern coastal areas of North America,
Europe, Asia, and on the land masses of Greenland
and Antarctica.
• Example: Barrow, AK
A - Tropical
B - Dry C - Mid-latitude subtropical
D - Mid-latitude continental
H - Highlands
Factors that Influence Climate
• Solar radiation received at a particular latitude
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
• Heat exchange from ocean currents
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
• Heat exchange from ocean currents
• Distribution of mountain barriers
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
• Heat exchange from ocean currents
• Distribution of mountain barriers
• Pattern of prevailing winds
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
• Heat exchange from ocean currents
• Distribution of mountain barriers
• Pattern of prevailing winds
• Distribution of land and sea
Factors that Influence Climate
• Solar radiation received at a particular latitude
• Air mass influence
• Location of global high and low pressure zones
• Heat exchange from ocean currents
• Distribution of mountain barriers
• Pattern of prevailing winds
• Distribution of land and sea
• Altitude
Influences to weather patterns by other natural
re-occurring climate cycles
• El Niño
• La Niña
• Drought
• Monsoon
Normal Conditions
• Strong easterly trade winds in the tropical Pacific push surface
waters toward the west.
• Waters heat up more as they move toward the western Pacific
Ocean because of longer sun exposure.
• Cooler waters off the coast of Peru in the eastern Pacific due to
upwelling.
El Niño Conditions
• Weaker easterly trade winds in the central and eastern
Pacific Ocean.
• This causes the normal upwelling of the cold water from
below the surface to stop and the warm surface water to
remain.
Affects of El Niño
• Impacts to the continental US:
•Temperatures in the winter are warmer than
normal in the North Central States and cooler
than normal in the Southeast and the Southwest.
• Increase in the rainfall across the southern United
States from Texas to Florida.
• Increase in upper level winds over the Atlantic which
could cause fewer hurricanes.
El Niño
El Niño Years
Typically occur every 3 to 5 years and last about
one year.
•
•
•
•
•
•
•
•
•
•
•
•
1902-1903
1905-1906
1911-1912
1914-1915
1918-1919
1923-1924
1925-1926
1930-1931
1932-1933
1939-1940
1941-1942
1951-1952
•
•
•
•
•
•
•
•
•
•
•
•
1953-1954
1957-1958
1965-1966
1969-1970
1972-1973
1976-1977
1982-1983 (Major event)
1986-1987
1991-1992
1994-1995
1997-1998 (Major event)
2002-2003
• 2006-2007
La Niña Conditions
• Stronger than normal easterly trade winds in the central
and eastern Pacific Ocean.
• This causes more upwelling off the western coast of
South America resulting in cooler than normal surface
water across the eastern equatorial Pacific Ocean.
Affects of La Niña
• Impacts to the continental US:
• Wetter than normal conditions across the Pacific
Northwest.
• Drier and warmer than normal conditions across
much of the southern United States.
• Decrease in upper level winds over the Atlantic which
could increase hurricane activity.
La Niña
La Niña Years
Typically occur every 3 to 5 years and last about
one year.
•
•
•
•
•
•
•
•
•
•
•
1903-1904
1906-1907
1908-1909
1916-1917
1920-1921
1924-1925
1928-1929
1931-1932
1938-1939
1942-1943
1949-1950
•
•
•
•
•
•
•
•
•
•
•
1954-1955
1964-1965
1970-1971
1973-1974
1975-1976
1988-1989
1995-1996
1998-1999
2000-2001
Early 2006
Late 2007-2008
Drought
A period of abnormally dry weather sufficiently prolonged for the lack
of water to cause serious hydrologic imbalance in the affected area.
Drought
A period of abnormally dry weather sufficiently prolonged for the lack
of water to cause serious hydrologic imbalance in the affected area.
Causes serious problems such as crop damage and/or water supply
shortages.
Drought
A period of abnormally dry weather sufficiently prolonged for the lack
of water to cause serious hydrologic imbalance in the affected area.
Causes serious problems such as crop damage and/or water supply
shortages.
Severity of drought depends upon the degree of moisture deficiency,
the duration, and the size of the affected area.
Monsoon
A period of seasonal winds; strongest on the southern and eastern
sides of Asia.
Monsoon
A period of seasonal winds; strongest on the southern and eastern
sides of Asia.
Monsoon climate -- Type of climate found in regions subject to
monsoons and characterized by a dry winter and a wet summer.
Monsoon
A period of seasonal winds; strongest on the southern and eastern
sides of Asia.
Monsoon climate -- Type of climate found in regions subject to
monsoons and characterized by a dry winter and a wet summer.
For example, India’s southwest monsoon lasts from June to
September and brings vital rain for the country’s farmers, but it also
causes massive destruction, floods, mudslides, collapsing houses,
and lightning strikes killing hundreds of people each year.
Using Climatology to Study
Specific Weather Events
Tropical Cyclones
Floods
Droughts
Winter Storms
Tornadoes
Rainfall
Snowfall
Temperatures
For Example:
Tropical Cyclone Climatology
in the Atlantic
Atlantic Basin Category 5 Hurricanes
31 Category 5 Hurricanes have occurred since 1900
Lowest Pressure –
Hurricane Wilma 2005 - 882 mbs
Atlantic Basin Category 5 Hurricanes
31 Category 5 Hurricanes have occurred since 1900
Lowest Pressure –
Hurricane Wilma 2005 - 882 mbs
Highest maximum sustained winds –
Hurricane Allen 1980 - 165 Knots
Atlantic Basin Category 5 Hurricanes
31 Category 5 Hurricanes have occurred since 1900
Lowest Pressure –
Hurricane Wilma 2005 - 882 mbs
Highest maximum sustained winds –
Hurricane Allen 1980 - 165 Knots
Most Category 5 Hurricanes per season
2005 – (Four) – Emily, Katrina, Rita and Wilma
1961 – (Two) – Carla and Hattie
1960 – (Two) – Donna and Ethel
2007 - (Two) - Dean and Felix
Hurricane Strikes on the United
States Mainland 1851-2006
Category
Strikes
5
3
4
18
3
75
2
73
1
110
TOTAL 279
Major
96
Category 3 or higher at landfall
Hurricane Strikes in Texas 1851 to 2007
Category
Texas
[North]
[Central]
[South]
USA
1
2
3
4
5
All
Cat 3+
24
13
7
7
18
7
5
7
12
3
2
7
7
4
2
1
0
0
0
0
61
27
16
22
19
7
4
8
110
73
75
18
3
279
96
Top Ten Known Most Intense Texas Hurricanes
Based on Pressure at Landfall
1886
1919
1961
1900
2005
1932
1957
1915
1970
1980
Indianola
South Texas
Hurricane Carla
Galveston
Hurricane Rita
N Texas
Hurricane Audrey
Galveston
Hurricane Celia
Hurricane Allen
925 mbs
927 mbs
931 mbs
936 mbs
937 mbs
941 mbs
945 mbs
945 mbs
945 mbs
945 mbs
Last Direct Hit of a major hurricane within 75
nautical miles of the location indicated.
Brownsville, Texas
Central Padre Island
Corpus Christi, Texas
Port Aransas, Texas
Matagorda, Texas
Freeport, Texas
Houston, Texas
Beaumont, Texas
1980 Hurricane Allen
1999 Hurricane Bret
1970 Hurricane Celia
1970 Hurricane Celia
1961 Hurricane Carla
1983 Hurricane Alicia
1983 Hurricane Alicia
2005 Hurricane Rita
– Cat 3
– Cat 3
– Cat 3
– Cat 3
– Cat 4
– Cat 3
– Cat 3
– Cat 3
Climate Change on Earth is a fact of life.
Through out Earth’s history, the climate has varied.
Reflecting the complex interactions and dependencies
of the solar, oceanic, terrestrial, atmospheric and
living components that make up planet Earth’s systems.
It is the belief, f or the last million years, earth has
experienced cycles of warming and cooling that take
approximately 100,000 years to complete.
During each cycle, global average temperatures most likely
have fallen and risen 9 deg F (5 deg C) each time.
This took the Earth into an ice age and then warming it
again.
These cycles are believed to be associated with regular
changes in the Earth’s orbit that alter the intensity of
Solar energy the planet receives.
Another process that can change the Earth’s climate
abruptly is a shift in the oceans circulations. This
can happen due to a massive volcanic eruptions.
Climate has changed throughout geological history.
There have been many natural reasons:
•Changes in the Sun’s energy received by the Earth
due to slow orbital changes
•Changes in the Sun’s energy reaching the Earth’s
surface due to volcanic eruptions.
The sun is the most powerful driving force
on the Earth’s climate.
Solar variability is the main cause of climate change.
When the sun activity is low, the cooler the Earth’s
temperature. The more active the sun, the higher the
Earth’s temperature.
The climate is always changing in
response to the influences of the sun and
the orbit of the sun.
The climate is always changing in
response to the influences of the Sun and
the orbit of the Sun.
Climate change is the result of
• Earth's orbital eccentricities,
• Earth’s axial wobble,
• Solar brightness variation,
• cosmic ray flux, etc..
The climate is always changing in
response to the influences of the Sun and
the orbit of the Sun.
Climate change is the result of
• Earth's orbital eccentricities,
• Earth’s axial wobble,
• Solar brightness variation,
• cosmic ray flux, etc..
Other terrestrial drivers of climate change
include:
• Super volcanic events
• Tectonic movement
Variations in the earth’s orbital characteristics
Eccentricity: The shape of the Earth’s orbit around the
sun. Over a 100,000 year period, the orbit changes from
being elliptical to nearly circular and back to elliptical.
The greater the eccentricity [more elliptical] the greater
variation in solar energy at the top of the atmosphere.
Currently we are in a period of low eccentricity.
Precession of the Equinox: the wobble of the earth as
it rotates on its polar axis.
This changes the orbital timing of the equinoxes and
solstices.
This precession has a cycle of 26,000 years. The Earth is
closer to the sun in January [perihelion] and farthest from
the sun in July [aphelion].
Obliquity - Changes in the tilt of the earth’s Axis a rotation
of 41,000 years.
During these 41,000 years the tilt changes from 22.5
degrees to 24.5 degrees.
When the tilt is small there is less climatic variation
between summer and winter seasons in the middle and
high latitudes.
Obliquity - Changes in the tilt of the earth’s Axis a rotation
of 41,000 years.
During these 41,000 years the tilt changes from 22.5
degrees to 24.5 degrees.
When the tilt is small there is less climatic variation
between summer and winter seasons in the middle and
high latitudes.
Periods of large tilt result in
greater climatic variation in the
middle and high latitudes.
Winter tend to be colder and
summers warmer.
Currently the tilt is 23.5 degrees.
http://www.ncdc.noaa.gov/paleo/slides/slideset/11/11_183_bslide.html
Solar activity was lowest during the 17th Century, when
Earth was most frigid.
In 1996, near the last solar minimum, the Sun is
nearly featureless. By 1999, approaching
maximum, it is dotted by sunspots and fiery hot
gas trapped in magnetic loops.
Solar max has also been tied to a 2 percent
increase in clouds over much of the United
States.
Sunspot data going back several
hundred years showed that fewer
sunspots signaled a cold period which could last up to 50 years but that over the past century their
numbers had increased as the
earth's climate grew steadily
warmer.
Sunspot data going back several
hundred years showed that fewer
sunspots signaled a cold period which could last up to 50 years but that over the past century their
numbers had increased as the
earth's climate grew steadily
warmer.
The scientists also compared data from ice samples
collected during an expedition to Greenland in 1991. The
most recent samples contained the lowest recorded levels
of beryllium 10 for more than 1,000 years.
Beryllium 10 is a particle created by cosmic rays that
decreases in the Earth's atmosphere as the magnetic
energy from the Sun increases. Scientists can currently
trace beryllium 10 levels back 1,150 years.
For the last 10,000 years [the span of human civilization
the Earth’s climate has been relatively stable.
Regional variations in climate patterns have influenced
human history in profound ways. These variations have
played important roles in whether a society thrived or
failed.
Cool climatic conditions have prevailed during the past
1,000,000 years. The species Homo sapiens evolved under
these climatic conditions.
Warm Periods - Interglacial Periods
Over the past 415,000 years there have been 4 warm periods
1450 -1300 BC
Minoan Warm Period
250-0 BC
Roman Warm Period
800-1100 AD
Medieval Warm Period
1900-2010 AD
20th Century Warm Period
Other period are cool periods - Glacial Periods
The early part of the 20th century was much colder than it
is today.
A consequence of these colder temperatures is that there
are changes in sea currents and temperatures and in the
strength and direction of the winds at sea.
As a result, large icebergs from the Greenland ice sheet
would often drift southward into the Atlantic Ocean and
into the shipping lanes between Europe and America.
It was much more likely that a vessel would encounter
icebergs back in the early part of the century than it is
now. This is in part a consequence of a cooler climate 80
years ago.
In a scientific paper, written on
the subject of the weather on
that night in 1912 when the
Titanic struck an iceberg and
sunk, E. N. Lawrence
concludes that there is a link
between sunspots and the
icebergs found in shipping
lanes in the early 1900s.
Colonies developed in Greenland 1,500 years ago.
Earth’s climate is influenced by interactions involving
the Sun, ocean, atmosphere, clouds, ice, land, and life.
Climate varies by region as a result of local
differences in these interactions.
Covering 70% of the Earth’s surface, the ocean exerts
a major control on climate by dominating the Earth’s
energy and water cycles.
The oceans have the capacity to absorb large amounts
of solar energy.
.
Heat and water vapor are re-distributed globally
through density-driven ocean currents and
atmospheric circulation.
Changes in the ocean circulation caused by tectonic
movements or large influxes of fresh water from
melting polar ice can lead to significant and abrupt
climate change, both locally and on global scales.
Solar power drives Earth’s climate. Energy from the
Sun heats the surface, warms, the atmosphere, and
powers the ocean currents.
GLOBAL CLIMATE CHANGE
Things we don’t know!
We do not have a long record of global temperatures.
We do not know the mean temperature over the globe
over time in order to know if we are below or above
normal.
GLOBAL CLIMATE CHANGE
Things we don’t know!
We do not have a long record of global temperatures
We do not know the mean temperature over the globe
over time in order to know if we are below or above
normal.
We do not know which comes first more CO2 or higher
temperatures. Some graphs show that rise in CO2 lags
behind the rise in temperature by 100 years.
BRIEF PERIOD OF TIME IN THE EARTH’S HISTORY
Humans have only been trying to measure the temperature
fairly consistently since about 1880, during which time we
think the world may have warmed by about +0.6 °C ± 0.2 °C.
The estimate of warming is less than the error margin on our
ability to take the Earth's temperature, generally given as 14
°C ± 0.7 °C for the average 1961-1990 while the National
Climatic Data Center (NCDC) suggest 13.9 °C for their
average 1880-2004.
Our cities have grown and most of the observations
are now influenced by the heat island with fewer
observations in rural areas. Could this explain the
increases temperatures in some areas?
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
Man cannot stop the natural warming cycle.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
Man cannot stop the natural warming cycle.
Sea level heights have been higher in the past.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
Man cannot stop the natural warming cycle.
Sea level heights have been higher in the past.
The globe has been warmer in the past.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
Man cannot stop the natural warming cycle.
Sea level heights have been higher in the past.
The globe has been warmer in the past.
The globe has been ice free in the past.
GLOBAL CLIMATE CHANGE
What we know!
Climate change is a natural cycle. The globe has
warmed and cooled many times.
The human contribution to warming is insignificant.
Man cannot stop the natural warming cycle.
Sea level heights have been higher in the past.
The globe has been warmer in the past.
The globe has been ice free in the past.
The globe will cool again.
GLOBAL CLIMATE CHANGE
What we know!
Carbon dioxide is not a pollutant.
GLOBAL CLIMATE CHANGE
What we know!
Carbon dioxide is not a pollutant.
Increased atmospheric levels of CO2 benefit plant
growth, agriculture and forestry.
GLOBAL CLIMATE CHANGE
What we know!
Carbon dioxide is not a pollutant.
Increased atmospheric levels of CO2 benefit plant
growth, agriculture and forestry.
Climate models overestimate the warming effects
of greenhouse gases by ignoring negative feedbacks from clouds and water vapor that would
greatly reduce the warming effects.
GLOBAL CLIMATE CHANGE
What we know!
Carbon dioxide is not a pollutant.
Increased atmospheric levels of CO2 benefit plant
growth, agriculture and forestry.
Climate models overestimate the warming effects
of greenhouse gases by ignoring negative feedbacks from clouds and water vapor that would
greatly reduce the warming effects.
Observed climate warming (and cooling) appear to
be controlled by natural factors - principally the
variability of the solar emissions and solar
magnetic fields.
Each year 186 billion tons of CO2 enters the Earth’s
atmosphere.
90 billion tons come from biological activity in the
earth’s oceans
90 billion tons come from sources such as
volcanoes and decaying plants
6 billion tons from human activity
CO2 is a nutrient not a pollutant. All life, plants and
animals benefit from it.
~99.72% of the “greenhouse” effect is due
to natural causes - water vapor and traces
of other gases.
Eliminating human activity altogether
would have little impact on climate
change.
Recent observations shows a cooling trend?
Focus should be on adapting to climate change
and cleaning the environment for healthy living.
1. Accept that the earth’s climate is continuously
changing
2. Continue to study the science of climate change and
understand what changes are coming
3. Continue to find ways to adapt to climate change
4. Continue to find ways to recycle
5. Continue to find ways not to pollute the air
6. Continue to find ways not to pollute the oceans
7. Continue to find ways to feed the population of the
world
8. Continue to find alternate fuels and energy
Humans need to engage in a grass root effort
where everyone is responsible for their piece of
earth and start from the area they live, to the
neighborhood, to the city, to the county, to the
state, to the country, to the world.
Weather Research Center
5104 Caroline St.
Houston, Texas 77004
713-529-3076
www.wxresearch.com
or
www.wxresearch.org