Download HSS_Interviews_09_28_08

HSS on Haiti Focus
Meeting Info:
Date:
September 28, 2008
Time:
7:30-8:00 AM
Place:
WMBR Radio 88.1 FM
Attendees:
Name
Cornely, Pierre-Richard
Brutus Leaderson
Title
HSS Public Relations Representative
HSS
Science Ak Progres
Sponsored by
The Haitian Scientific Society (HSS)
BRUTUS Section 1
In the last two shows we have had a lot of discussion on the subject of Global Warming.
Specifically, in the last show, we revisited the subject and we tried to explain to the audience
some of the parameters related to global Warming in some detail.
At the same time, the events of the last few weeks to a month has raised some serious questions
about possible connections between Global Warming and the state of the earth’s climate. Indeed
in the last month we have have three hurricanes strike the island and the united states and in most
cases the countries and areas on the path of these hurricanes have suffered considerable damages.
Specifically hurricanes Ike, Hanna and Gustav.
Questions are also currently being raised on the reasons for the unpredictable nature of the
hurricane seasons we have had in the last month.
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Today we would like to examine the physical and scientific nature, as well as the origin of these
huricanes.
On studio is Dr. Pierre-Richard Cornely who is going to help us navigate thorugh these many
questions when we come back.
BRUTUS – Section 2
First, could would like to go back over What Global Warming is, and Where it comes from?
Pierre-Richard Cornely – Section 2
When taking a more careful and deeper look at Global Warming we come across the following
observations:

The Earth's climate has been changing in response to external forces within the earth’s
atmosphere. These external forces include but are not limited to:
o
the variations of the earth’s orbit around the Sun (orbital forces)
o changes in solar flux, the increase proliferation of volcanic eruptions,
o and atmospheric greenhouse gas concentrations.

The detailed causes of the recent warming remain an active field of research, but the
scientific consensus is that the increase in atmospheric greenhouse gases due to human
activity caused most of the warming observed since the start of the industrial era.

This attribution is clearest for the most recent 50 years, for which the most detailed
scientific data are available.

Greenhouse gases play the role of heat retention in the atmosphere.
o When sunlight reaches the surface of the Earth,
o some of it is absorbed and warms the surface of the earth.
o The atmosphere absorbs the radiation from the sun.
o This warming effect of the earth’s atmosphere by the sun’s radiation keeping the
earth relatively warm enough to be habitable by humans is what is called the
“Greenhouse Effect”.

The variations in the concentration of greenhouse gases due to human interaction with the
earth’s atmospheric concentration is what causes the heat retention of the earth
atmosphere to increase and this global increase in heat is what we call Global Warming
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BRUTUS – Section 3
First, before we look at anything else, I would like for us to give the audience a better feeling for
the notion of weather. In particular we know that several of the people listening to us on the
radio have seen or heard about the weather man on television. They may have probably seen
several discussions about the weather by the weather man using a weather map. Can you give the
audience some idea about what the weather map is using and the science behind the
interpretation of the weather map.
Pierre-Richard Cornely – Section 3

The weather is a set of all the phenomena occurring in the earth’s atmosphere at a given
time.

Weather refers to the current activity in the earth’s atmosphere, as opposed to the term
climate, which refers to the average atmospheric conditions over longer periods of time.

Weather occurs due to the density (temperature and moisture) differences between one
place to another.
o These differences can occur due to the sun angle at any particular spot, which
varies by latitude from the tropics.
o The strong temperature contrast between polar and tropical air gives rise to the jet
stream.
o Weather systems in the mid-latitudes, such as extratropical cyclones, are caused
by instabilities of the jet stream flow.
o Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at
different angles at different times of the year.
o On Earth's surface, temperatures usually range ±40 °C (±72 °F) annually. Over
thousands to hundreds of thousands of years, changes in Earth's orbit affect the
amount and distribution of solar energy received by the Earth and influence longterm climate as well as short term weather.

Meteorologists such as the weather man you see on TV use a weather map to view and
interpret the weather elements that are dominating any particular short time interval (
usually 1-3 days) over a geographical area based on information from ground-based
weather instruments.

Weather maps are created by plotting the values of sea level pressure, temperature, and
cloud cover onto a geographical map to help find synoptic scale (large scale or cyclonic
scale is a horizontal length scale of the order of 1000 kilometres (about 620 miles) or
more) features such as weather fronts (A weather front is a boundary separating two
masses of air of different densities, and is the principal cause of meteorological
phenomena.)

Weather maps have special symbols which show frontal systems, cloud cover,
precipitation, or other important information.
o For example, an L may represent low pressure – Low Pressure represents hot air
that is moving from the earth’s surface, for example at the equator, to the higher
latitudes. As the air move to the higher latitudes towards the North Pole, it cools
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off therefore its pressure increases. The low pressure system is usually followed
by good and fair weather.
o An H on the other hand may represent High pressure – High Pressure represents
hot air that is moving from the higher latitudes to the earth’s surface. As the air
move to the lower latitudes towards the Equator, it warms off therefore its
pressure increases. This weather front usually corresponds to precipitation and
rain.
o Various symbols are used not just for frontal zones and other surface boundaries
on weather maps, but also to depict the present weather at various locations on the
weather map. Areas of precipitation help
BRUTUS – Section 4
I am sure the audience will have a better appreciation for the weather presentations they see on
TV. Hopefuly members of the audience are taking note so that they can be better prepared to
interpret and understand the presentations by the weather man on TV in the future.
Now that you have told us a bit more about weather system and what the weather is, we would
like to understand more about the nature of hurricanes.
What is a hurricane? Where does it come from?
Pierre-Richard Cornely – Section 4

Originally derived from the word huracán from the Aztez civilization first adopted by the
Spanish.

Hurricane most commonly denotes a tropical cyclone. The term is most often used for
cyclones occurring in the Atlantic and eastern Pacific Oceans.

Next, we need to better understand what a tropical cyclone is
o A tropical cyclone is a storm system
o The term "tropical" refers to both the geographic origin of these systems, which
form almost exclusively in tropical regions of the globem, what are usually called
“the Tropics”.
o The Tropics form a series of regions of the globe that are centered on the equator
at approximately 23°26' (23.4°) N latitude, and in the southern hemisphere at
23°26' (23.4°) S latitude. This region is also referred to as the tropical zone and
the torrid zone
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
Going back to the definition of a storm
o A storm is any disturbed state of an astronomical body's atmosphere, especially
affecting its surface, and strongly implying severe weather.
o It may be marked by strong wind, thunder and lightning (Lightning is an
atmospheric discharge of electricity), a thunderstorm or heavy precipitation.
o Storms are created when a atmospheric center of low pressure develops, with a
system of high pressure surrounding it.
o This combination of opposing forces create winds (i.e., movemnt of air) and result
in the formation of storm clouds.

A cloud is a visible mass of droplets or frozen crystals floating in the
atmosphere above the surface of the Earth.

Depending on their location and strength, tropical cyclones are referred to by other
names, such as hurricane, typhoon, tropical storm, cyclonic storm, tropical
depression and simply cyclone.

While tropical cyclones can produce extremely powerful winds and torrential rain, they
are also able to produce high waves and damaging storm surge.
o They develop over large bodies of warm water, and lose their strength if they
move over land.
o This is the reason coastal regions can receive significant damage from a tropical
cyclone, while inland regions are relatively safe from receiving strong winds.
o Heavy rains, however, can produce significant flooding inland, and storm surges
can produce extensive coastal flooding up to 40 kilometres (25 mi) from the
coastline.
o Although their effects on human populations can be devastating, tropical cyclones
can also relieve drought conditions.

Many tropical cyclones develop when the atmospheric conditions around a weak
disturbance in the atmosphere are favorable. Tropical systems are then moved by steering
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winds in the troposphere; if the conditions remain favorable, the tropical disturbance
intensifies, and can even develop an eye.

On the other end of the spectrum, if the conditions around the system deteriorate or the
tropical cyclone makes landfall, the system weakens and eventually dissipates. In spite of
this, it is not possible to artificially induce the dissipation of these systems with current
technology.
BRUTUS – Section 5
I am sure that the audience is happy to hear about your description of the hurricanes but I am
also sure that our audience want to know why Haiti. Why is it that Haiti seems to be more
susceptible to hurricanes and cyclones? Why is it that these hurricanes are taking place at the
same time of the year, for example between the summer and the fall?
Pierre-Richard Cornely – Section 5

Haiti is placed at the center of the Tropics, as we have discussed before. Because we are
in the center of the tropics, it is more likely that cyclones and hurricanes will develop in
and around Haiti.

The other point about Haiti is that it is a coastal region, and as such when hurricanes take
place, they have a tendancy to create movement of water. This movement of water
creates high waves that in terms create flooding.

In addition, Haiti has a severe problem of deforestation. This problem has worsen over
the years due to the fact that wood is what is used to create charcoal in Haiti. The wood
that is removed weakens the earth’s roots and foundations and alloes air to move freely
about the surface of the earth.

The weakening of the earth’s crust makes it easy for mudslide to occur

The movement of air facilitates the destruction of property that is exposed to its path.

Scientific studies on the occurrence of hurricanes in the Tropic clearly show that there is
a close correlation with air pressure. Air pressure is most variable when hot air is moving
from the lower latitudes to the higher altitudes which occurs most likely between the
summer and the fall.

Several solutions can be applied to the problem and difficulties that Haiti is confronting
with hurricanes
o Replenish the trees, this will strengthen the earth and prtect the country from
themovement of air, this will be like a prevention system
o Develop an alert system that can predict the movement of storm systems and
predict the occurrence of hurricanes and cyclones.
o This ptrediction system can be sued to warn the people so that they can have
enough time to protect themselves
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BRUTUS – Section 6
You have described a little bit about how hurricanes occur and why they all seem to take place in
a particular regions of the globe. Your description points to the fact that these hurricanes will
always most likely occurs in the tropical zones and as such countries in the carribean and south
america will always be more likely to be impacted.
However, some people are still wondering if the occurrence of these hurricanes as well as their
unwieldy behavir has something to so with Global warming. Can you provide any additional
information to the audience abouth this possible connection?
Pierre-Richard Cornely – Section 6
There is no scientific evidence that we have at the moment that directly relates Global warming
to the occurrence of hurricanes
Scientist have hinted at a possible connection without supporting evidence. At present a lot of
work is being done to develop the evidence required if it exist in order to establish such
correlation.
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