Isaac+Journal

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Chapter One Summary. Sunday, August 29th, 2010
It is obvious that the Earth itself is warming. In response to such changes, weather patterns are changing dramatically. The enormous impact that such changes have had and will have will change almost everything that we do on a daily basis, regardless of whether the changes are manmade or not. This, ultimately, is the question: is it we who are doing this?

An important distinction to make when discussing Global Warming and its effects on climate and weather is the difference between the two. Weather is highly variable and somewhat entropic by nature. The daily occurrences are foreseeable to a point, but their predictability diminishes rapidly the farther into the future forecast is. Climate is the average of the weather; it is an average that makes the seemingly random happenings of daily weather more understandable.

Since weather is so variable, the only way to have accurate predictions about the future is to use our knowledge of the past and present climate changes and apply it to the future. The major factors that affect climate as far as Global Warming are the amount of energy coming to Earth from the Sun, the amount of Greenhouse Gases in the atmosphere and the impact of the modern human civilization. Almost everything we do on a daily basis nowadays is in some way connected to some sort of emission or other cause that effects Global Warming. However, what makes forecasting for the upcoming century especially hard is our relative lack of data about the Earth’ climate in the past. Some parts of the Earth take a long time to change, such as the warming of a deep ocean or the melting of vast sheets of ice. Our lack of knowledge of how those things happen makes the future climate especially hard to predict.

Clearly the presence of Greenhouse Gases in the atmosphere are enabling the Global Warming process. If we as humans could reduce, and ideally eliminate our Carbon Dioxide emissions eventually, we would be making a large step in the right direction. We are releasing the stored energy of millions of years in a comparatively miniscule amount of time, however it is hard to stop organizations, countries and companies from emitting Carbon Dioxide when they have such a vested interest in the continuing use of Fossil Fuels.

Mankind is having a recognizable effect on global climate and weather. The monetary cost of Global Warming in the long run is much more than that of stopping it. The Kyoto Protocol will help cut emissions by about 6% below 1990 levels, however studies show that cuts of over 50% would be necessary to counteract the current levels of Carbon Dioxide and other Greenhouse Gases.

Tuesday, September 7th, 2010.
In the video “Atmosphere” from The Habitable Planet series, the viewpoints of two different divisions of climate research are presented. The first is Dr. Pieter Tans, part of NOAA’s Global Monitoring Division. Tans focuses on greenhouse gases, the contributing factors to the presence of Carbon Dioxide, and its effect on global climate. The second is Prof. Kerry Emanuel, from M.I.T. His main study is of hurricanes and their effect on weather systems, the oceans, and global climate overall. Tans uses a vast network of atmospheric monitoring systems to have a overall view of what global carbon dioxide levels are. He is researching the relationships of carbon dioxide sources and sinks in the world and especially in North America. His goal is to learn more about how the delicate balance between sinks and sources works, how the extra man-made carbon dioxide is effecting this balance, and what can be done with the natural system to possibly decrease the levels of carbon dioxide in the air. The other thing he is doing is collecting data from specific areas, such as downwind from cities or forests, to learn more on the smaller scale. Emanuel stumbled on the questions that prompted his research when he attempted to further educate himself about hurricanes. He noticed that hurricanes are mostly overlooked in their effect on the oceans and the climate. He postulates that hurricanes might be involved more heavily with climate systems then one might have otherwise thought. The tight relationships between the surface temperature of the ocean water and the power of the storm is mostly known, however the “stirring” mechanism and the cooling effect that hurricanes leave behind is really what Emanuel is working on currently. Tans and Emanuel go about their research in a very different way. Tans is very global and avidly collects hundreds of samples a day about his vast research subject. Emanuel, on the other hand, does not have that luxury, and thus uses extensive models to further understand hurricanes with only little data from actual hurricanes. Luckily, the differing methods suit each line of research well. Air is plentiful and can be collected rather easily. However, hurricane data is much harder to come by, and the modeling data is quick and accurate. The differences in their questions and their research methods differ quite a bit, however the overall questions that they are attempting to answer with their research are very similar. Climate change is their focus, and in this changing world, it is a very avidly researched field with many sub-fields. Therefore their differences are not surprising, though the hurricane findings are refreshingly new in the field of climate change.

Isaac: You started out strong but lost the thread a bit in the last two paragraphs. Details are going to be more and more important to your assignments as you start to hone in on a research question. Be as observant as possible about how other researchers identify their research questions and then tightly link their tools they use to the research question.

Wednesday September 22nd, 6:47 am
§ What is the research question being asked by this project? This project is focused on finding out how Hurricanes effect climate overall and how we as humans can become better at predicting these storms. Some of the most important questions within this project are: “what effects the strength of hurricanes?”, “how do they alter the climate?”, “what do we not understand fully about their working and how can we understand?”, among other questions.

§ What are the methods being used to answer those research questions? Professional researchers use extensive modeling software, as seen in one of our videos, to analyze the data collected about previous hurricanes. The methods for data collection include live data from hurricanes that hit from planes, satellites, or the ground.

§ What data or information has been collected to date? The data that I will have access to is a compiled database of past hurricanes in G.I.S. software. This database includes wind speeds, satellite imaging, thermal scans of surface temperature, and other data. The other data that I might be able to use comes from the internet – wind speeds, amount of rain, hurricane rankings, etc – that are made about hurricanes that I may or may not have in my database.

§ What might the next step, your next step be? \My next step would be to form a working hypothesis and organize the general direction that I (or we, depending) want the research to go. From there the next step would be to begin to educate myself thoroughly on the topic, from the physics of hurricanes, to the chemistry of the molecules, to the geothermal impact of the hurricane itself. Then I would apply that knowledge to the database and attempt to find enough trends to begin to be able to predict hurricanes based on their formation/growth climate conditions, or something similar to that.



Hurricane Formation - Octovber 6th
Hurricanes start with the combination of thunderstorms and a low-pressure center. This is called Tropical Disturbance. Given enough time and the right conditions – namely warm, moist air – the Disturbance can turn into a Tropical Depression. After Depression comes Tropical Storm, and then Tropical Cyclone, also known as a Hurricane. Hurricanes are what is called a “heat engine”. Heat engines convert heat into mechanical work, manifested in hurricanes by the enormous winds, rain, and waves. The Hurricane itself is a massive storm, but can be thought of as layers of thunderstorms spinning according to the hemisphere (counterclockwise in the northern and clockwise in the southern) due to the Coriolis Effect. In the very center is the eye of the hurricane, which can be up to twenty miles in diameter, however it is important to note that as the intensity of the storm increases, the wind speed increases and this pulls the eye in, making the diameter smaller. Next is the eye wall. The eye wall contains the hurricane’s most destructive powers. It can be fifteen miles wide and can produce //sustained// winds in excess of 155 miles per hour, which is the minimum for a Class 5 storm. Another part of the hurricane is the rain shield, which is a mainly solid sheet of rain that intensifies the closer you get to the eye. The spiral rain bands are the bands of clouds that are unmistakable in hurricanes. These are due to one of the most important triggers for the formation of hurricanes: the Coriolis Effect.

The Coriolis Effect is due to the rotation of the Earth. It is a force of inertia that is apparent when Newtonian Laws are applied to objects and their movement in relation to a spinning coordinate axes: the rotating Earth. The Coriolis Effect drives the spinning effect and ultimately dictates how the hurricane looks and works. The spinning effect pulls warm, moist air towards the center, where it is pulled up the middle by the spinning. By the time it reaches the top of the storm, the heat energy and moisture has been pulled out, and the warm, moist air has been stripped down to cold wind. The cold wind drives the top of the hurricane until it falls from the side of the Hurricane onto the warm water, where it once again becomes warm, moist air. These top winds are very important because too much upper wind can effectively seal off the eye “tunnel”, making it so there is nowhere for the air and moisture to escape. This backs up the whole engine, and can cause the storm to lessen in intensity or even cause it to subside. A good example of a similar phenomenon is when you stick a potato in a car’s muffler; closing off the exhaust stops the engine from working.

With a knowledge of how hurricanes work on the basic level, we can now pursue a somewhat broader understanding of what exactly inhibits and triggers hurricanes. Hurricanes are weakened especially by the upper winds mentioned above, and lack of fuel –Warm, moist air. However there are other weakening factors such as the sinking effect that occurs at about twenty degrees latitude called the Trade Wind Inversion. Cold air higher in the atmosphere sinks down, making it so that there is a direct relationship between altitude and temperature in certain parts of the atmosphere, the inverse of what it is normally. This effect hinders hurricanes by providing colder air at lower altitudes creates strong upper-level winds that have the potential to rip apart hurricanes.

Scientists are more interested in what causes hurricanes than what slows or stops them, and are thus still exploring how hurricanes form and how each of the factors they have identified enables or inhibits hurricane formation. A big trigger of hurricanes is the Easterly Trade Winds where the Northern and Southern Hemispheres meet. These winds cause multiple daily thunderstorms in what is called the Intertropical Convergence Zone (ITCZ). Some storm systems break off of the ITCZ and can form more organized storms. Though the Coriolis Effect limits where and when these storms can organize into hurricane form because the Effect itself has little or no effect before you get eight degrees away from the equator (north or south). Another trigger for hurricanes comes from over the Sahara. There is a jet of air that is part of the Saharan Air Layer (SAL) that exists due to the temperature differences between the Sea of Guinea and the Sahara Desert. Every three to five days during hurricane season what is called an “Easterly Wave” blows through the jet of air out towards the Atlantic.(Oddly, this jet of air and the Easterly Waves are also bent by the Coriolis Effect, which is ultimately what allows them to happen.) These Easterly Waves can be thought of as “bubbles” or “kinks” in the jet. The two quicktime files included below show an Easterly Wave and the clouds it creates (it helps if you watch them in order –it is easier to see what happens in the first one). At “July 31, 20:00” in the first animation you see the “kink” or “bubble” form and, then you can see as it spreads out over the Atlantic Ocean (continental boundaries are blue lines). The second is the exact same animation, it just contains a wider view. One of NASA and NOAA’s recent research endeavors is about the SAL and how it effects hurricanes. They have come to the conclusion that the frequency and intensity of Saharan Dust Storms is inversely proportional to that of hurricanes in the Atlantic. As we can see by the picture in the Air-Worldwide webpage, dust storms are not as simple as that. We see a Thunderstorm Complex following the Dust Storm out to the Atlantic, towards the Americas. If this thunderstorm got enough warm moist air, it could easily form into a Tropical Depression or Storm. [|Saharan Jet Animation One] [|Saharan Jet Animation Two] [|Dust Storm]

** Bibliography **
1. National Earth Science Teachers Association. "How Hurricanes Form." //Windows to the Universe//. Web. 04 Oct. 2010. . 2. Houston O.E.M. "Hurricane Formation." //Houston Office of Emergency Management//. 2008. Web. 06 Oct. 2010. . 3. Graham, Steve, and Holli Reibeek. "Hurricanes: The Greatest Storms on Earth : Feature Articles." //NASA Earth Observatory : Home//. Ed. Paul Przyborski. 01 Nov. 2006. Web. 06 Oct. 2010. .  4. Dailey, Peter S. AIR Director of Atmospheric Sciences. "AIR Worldwide: The Saharan Air Layer and Hurricane Formation." //AIR Worldwide: Homepage//. 07 Nov. 2006. Web. 06 Oct. 2010. .