Post on 07-May-2015
Trey Miller
Perspectives on Nature and the Environment
Dr. McGinley
Explain the cause of global warmingExplain the facts about natural
disasters and other unusual weather patterns
Explain what humans are doing to cause changes in weather patterns
Explain the effects of global warming on natural phenomena
IPCC – Intergovernmental Panel on Climate Change - reviews the latest scientific findings and writes a report summarizing global warming.
Natural Processes alone are NOT causing global warming
GHG’s (Greenhouse Gasses) emitted by humans are the only way to explain global warming
CO2 – Most prominent greenhouse gas contributing to global warming
Methane – one molecule of methane causes 20 times more warming than CO2
Nitrous Oxide – 300 times more powerful than CO2!
CFCs – 1000 times more powerful than CO2!
Since 1990, 20% increase in GHG’s emitted
The effects are not waiting for some far-flung future…
THEY ARE HAPPENING NOW
Could Just One Degree Change the World? - YouTube
Ice is melting worldwide, especially at the poles
Sea levels are expected to rise between 7 and 23 inches by the end of the century
Storm surge in Louisiana shows the effects of rising sea levels
Ecosystems will changeHurricanes and other storms are
likely to become strongerFloods and droughts will become
more common
Source: IPCC, 2007
An event is categorized as a natural disaster if it kills 10 or more people or leaves at least 100 people injured.
The number of natural disasters reported each year has been steadily increasing in recent decades, from 78 in 1970 to 348 in 2004.
Volcanic eruptionsEarthquakesLandslidesAvalanches
The frequency and severity of these types of disasters have remained steady in recent decades.
DroughtsTsunamisHurricanesTyphoonsFloods
These types of disasters have been increasing in frequency and severity for the past 25 years.
People are tempting nature with rapid urbanization in flood-prone regions
Increases the likelihood that their towns will be affected by flash floods and coastal floods.
Scientists believe the increase in hydro-meteorological disasters is due to human-caused factors.
Global warming is increasing the temperatures of Earth's oceans and atmosphere, leading to more intense storms of all types, including hurricanes.
Taiwan is the place on Earth most vulnerable to natural disasters, with 73 percent of its land and population exposed to three or more threats.
A hurricane is an intense tropical storm.
Form over warm tropical oceans (sea surface temperatures are above 80 °F)
Warm water evaporation causes very high humidity in the atmosphere.
This leads to thunderstorms. System of thunderstorms begin to
rotate
Energy from ocean heat also generates high winds.
The more heat available in the surface water, the more potential there is to generate heavy rain and high winds.
If wind speeds exceed 35 mph, the National Hurricane Center deems the system a tropical storm and assigns it a name.
A hurricane has sustained wind speeds of 74 mph or greater.
The National Hurricane Center categorizes hurricanes according to their maximum wind speed based on the Saffir-Simpson scale:
Saffir – Simpson Hurricane Scale
Category Wind Speed (mph) Storm surge (feet)
1 74 – 95 4 – 5
2 96 – 110 6 – 8
3 111 – 130 9 – 12
4 131 – 155 13 – 18
5 > 155 > 18
Hurricanes can spawn tornadoes and cause power outages in other locations
North Atlantic - there has been a clear increase in the frequency of tropical storms and major hurricanes.
This increase in frequency correlates strongly with the rise in sea surface temperature, and recent scientific studies link this temperature increase to global warming.
Several studies show a clear global trend toward increased intensity of the strongest hurricanes over the past three decades.
The strongest trends are in the North Atlantic Ocean and the Indian Ocean.
IPCC – “There is a human contribution to the observed trend of hurricane intensification since the 1970s.”
While Katrina was strengthening from a tropical storm to a category 5 hurricane, as it passed between the Florida Keys and the Gulf Coast, the surface waters were unusually warm - about 2 degrees F warmer than normal for that time of year.
According to the IPCC – Increases in precipitation are very
likely in high-latitudes.Decreases are likely in subtropical
regionsVery likely that heat waves, and
heavy precipitation will continue to become more frequent.
Sea level rise and increases in tropical storm activity will lead to damage as global warming continues.
Caused by an increase in particulates such as sulfate aerosols in the atmosphere due to human action.
Particles reflect sunlight back into space.
Creates a cooling effect that could possibly mask the effects of global warming.
Causes temperature irregularities between populated and unurbanized areas.
As the atmosphere seeks to balance extremes, violent weather phenomena occurs more frequently.
Pollution Super Cloud - Global Dimming
Earthquakes are seen as something outside of human control, but there is evidence that human activity can trigger minor events and at least one major event.
Nov. 6th, 1971 – a five megaton nuclear test bomb was fired underground in Alaska.
Triggered a major earthquake and a small tsunami.
The United States is not prepared to handle multiple catastrophic events in a short time period.
It can have profound influence on the entire ecosystem, including the human race and civilization.
Know what humans are doing to make weather and natural disasters worse.
Know the difference between natural geologic and hydro-meteorological disasters.
Be able to describe the effects of rising sea levels
Define global dimming
http://environment.nationalgeographic.com/environment/global-warming/?source=NavEnvGlobal
http://www.msnbc.msn.com/id/9731968/ns/technology_and_science-science/t/humans-add-natural-disaster-risk/
http://www.pewclimate.org/hurricanes.cfm
http://www.pewclimate.org/specialreports/katrina.cfm