engineering information technology : 2016-2017

Showing posts with label 2016-2017. Show all posts

Food Frontier

online engineering degree/engineering degree online/online engineering courses/engineering technology online/engineering courses online/engineering technician degree online/online engineering technology/electronic engineering online

This week in class we watched a video called “Food Frontier,” a project by Johns Hopkins Center for a Livable Future meant to showcase six projects around the U.S. working to increase access to healthy food. In class, we’ve been learning about gardening and the difference between local, organic foods versus imported and heavily processed foods. This video’s six very different stories about pioneering food projects added a lot to my learning by showing the varied and effective ways basically anyone can make a difference in their food community.

Community Access

In the video, a lot of different people were shown increasing their community’s access to food. They range from people in positions of power to the everyday citizen, but each played an important role in the positive changes made in their community.

One type of player is, to many people, the obvious one when the issue is of the social or political type -- the legislator. In the video, Representative Dwight Evans of Pennsylvania worked very hard to bring farmers markets to the ‘forgotten’ neighborhoods in Philadelphia, using his government position to effectively bring about the change.

Another channel for change in food communities are nonprofit organizations. Through the video, a number of nonprofit organizations, founded by regular people who wanted to fight for access to fresh, healthy food, were shown as successful changemakers.

Students also have great power to make change in their area. In the first story showcased in the video, a group of students in Cady, Nebraska, succeeded in building and running the first grocery store in their town, supplying the residents with easily attainable healthy food for the first time. Students may not be able to directly create change the way a legislator might or have the time and resources to found a nonprofit, but students are able to raise awareness in a very noticeable way and often have the drive and creativity to make change in unique and rewarding way.

Rural Food Desert

The first story in the video, the tale of Cady, Nebraska, introduced the concept of a rural food desert. A food desert is defined by the USDA as “living more than 10 miles from a grocery store.” According to the Rural Sociological Society, nearly 98% of these food deserts are in non-metropolitan areas -- and the rural food desert is born. These deserts occur as result of negative feedback loops. After World War II, rural populations started declining as urban areas began to grow. Because of this, grocery stores began to shut down, which in turn caused more rural residents to move to bigger cities, which caused even more grocery stores to shut down, etc. Eventually, this resulted in too few people in these areas to support a grocery store and retailers reluctant to cooperate with a grocery store “in the middle of nowhere.”

This, however, means the people remaining in these tiny rural areas are suddenly left, sometimes literally, high and dry. Suddenly, buying groceries -- something most of us take for granted -- can mean driving 40 miles or more to the closest store, which comes with high gas prices low-income or elderly residents may not be able to afford. As well, people living in rural food deserts often depend on canned, pickled, or non-perishable foods -- foods more processed and often sodium-rich.

One possible solution for people living in these rural food deserts or people working to fix these situations is to create gardens and non-commercial farms that provide local, fresh food that allow them to remain in their area with a self-sufficient, healthy diet.

Food Choice In A Community

In the video, each of the stories showed a way to encourage your community to make wiser, healthier decisions when it comes to shopping and eating.

In the video, the Philadelphia nonprofit worked to provide incentives for low-income shoppers to buy fresh produce, such as food stamp and food coupon bonuses at farmer’s markets. This was one effective way of encouraging healthy choices, because it made fresh food, usually the more expensive option, cheaper.

In Texas, they had another approach. The food nonprofit The Happy Kitchen invested in training normal people to be cooking educators, who then continued educating their community in an effective and engaging manner.

The final approach mentioned in the video was in multiple stories -- public money was put towards a Fresh Financing Initiative. This money was leveraged to make more money, which could be put to ensuring those communities had better access to fresh food.

These ideas inspired me to come up with my own ideas to encourage better food choices in communities. One way that might be successful would be to work with officials to regulate the distribution of fast food restaurants vs. organic grocery stores throughout a city, making the grocery store the easier, close option for the neighborhoods where there are currently none.

Another method, inspired by last week’s video, “What’s On Your Plate?” is the idea of a mass printed cookbook pamphlet, detailing easy-to-make, healthy meals, that can be distributed throughout the community.

Lastly, you could host food fairs, where farmer’s markets, organic grocery stores, and chefs could come together to create an event where the community could come together and sample and buy foods made from local produce, along with recipe cards that they could take home to try the healthy dish themselves.

School Food

In the video, two of the stories in the video were set in California -- both about school lunch.

In Claremont, for a long time, the food they provided for students every day was always prepackaged, processed, and frozen. The school district announced that given financial constraints and the need for minimal effort, they “couldn’t buy local food." In Riverside, however, the school is part of a food hub -- a system that connects farmers and school districts to provide thousands of children with fresh, locally grown food for lunch. These two schools provided examples of two ends of a spectrum -- the easy way, and the healthy way.

Image result for health vs unhealthy school lunch

Unfortunately, here at LJA, school lunch is closer to the Claremont side, though an effort has been made to make it otherwise. To students, it’s usually unappetizing -- under or overcooked, because of prepackaging and pre-freezing, the meat is often unidentifiable, and the milk is sometimes expired. However, an effort has definitely been made -- we do have a salad bar, minimal fast food, and food sourced in Minnesota.

The lunch, however, should be changed to a caterer that doesn’t just claim to be nutritious and palatably pleasing, but one that actually is. A major obstacle here is money. Currently, LJA can only afford our current caterer and quality of food, and unlike in Riverside, we live in Minnesota -- we’re not next door to a fruit orchard. To remedy the situation, students could help fundraise for LJA, or specifically raise awareness and funds for improving school lunch in particular. They could identify a local farm or organic caterer and use these funds to improve the health and taste of school lunch without straining the rest of the school’s budget.

What's On Your Plate?

This week in class we watched a film called What’s On Your Plate, following the story of Sadie and Safiyah, two girls exploring how the food options in Brooklyn impact the health and happiness of many different communities. In class, we’ve been learning about food environments and individual responsibility for food choices, so the video added a lot to our in-class learning. One interesting part of the film made me want to learn more about local CSAs -- my family goes to a weekly farmer’s market in the summer, but we haven’t looked for a CSA since we moved to the Twin Cities. One way I can make individual changes to my food impact would be to see whether we can find a new local CSA.

Food Environment

An important concept we learned about in class this week is the idea of a food environment. A food environment is a collection of factors that impact an individual’s food choices. They range from the individual level to the national level and can be separated into four specific aspects.

The first aspect is the individual factor. This can range from an individual’s food preferences -- for example, if you hate avocado, you won’t eat it, even if you know it’s good for you -- and their dietary restrictions: if you are lactose intolerant, for example, individual factors might prevent you from getting calcium from the usual sources.

The second aspect is the social environment. This can be your family, your friends, or any other community that creates an environment that impacts your food choices. For instance, if you like to go out to eat with your friends, you’re likely to eat at whatever fun place you go to, even if it might not be the healthiest, or, on the flipside, if all your friends are becoming vegetarians, you might as well. Another example of the social environment is the difference between how different families eat -- while another family might eat a more a traditional American meal, my family tends to eat different food, with, say, lentils and fish over bread and beef.

The third aspect is the physical environment. This refers to what, geographically, you have access to. If you live in a warmer climate, you might have better access to fresh fruits and vegetables year round. Or, maybe, you live on the coast, and therefore have easy access to fresh fish.

The fourth and final aspect is the policy environment. This is how the government impacts your food. One example of how the government impacts an individual’s food is school lunches -- many children, for twelve years of their life, attend schools that provide them with lunch and often breakfast as well. However, in public schools, it’s the government funding these school lunch programs and therefore basically deciding what is served -- usually the cheapest and most efficient foods rather than the healthiest. The government is also responsible for regulating the health and safety of food production -- they’re the ones who get say whether or not this chemical is safe in processed foods, or whether that farming practice should be legal.

One statement brought up in class, before and after we learned about food environments, was this idea that “individuals are responsible for their own food choices.” Originally, I agreed wholehearted with this statement -- after all, it seems that saying we aren’t is just an excuse to sit back and be lazy about our own health and food decisions. And, after learning about food environments, I still say that yes, I agree with this statement, but with a lot more thought behind that claim.

After all, three out of four of the aspects of the food environment seem out of our control. It’s not our decision what our family eats, at least when we’re children, or what our school serves us or where we live. Looking at it like that, it’s easy to say no, actually, individuals aren’t responsible for their food choices -- all these outside factors are.

However, for two reasons, I believe that they are. First, I want to highlight a key word in the statement: “individuals are responsible for their own food choices.” One definition of ‘responsible’ is ‘in control of,’ and yes, it’s possible to argue that we aren’t completely in control of the food available to us. However, the definition I prefer is ‘accountable.’ Even if we step back and say yes, there’s this and this and this that I can’t control, there’s still space for individual choice within all that. Your school lunch may be unhealthy, but why not go to the salad bar? Your friends may want to go out to a fast food place, but what’s the healthiest thing you can find on the menu?

Or, better yet, don’t go to the fast food place at all. The second part of my answer is that while we have these outside environments impacting our food environments, we still have the individual power to try to change them. You could convince your friends to go somewhere else or to come over and cook dinner with you instead. You could petition for better school lunches -- maybe not even at the school level but at the city government level. If the area you live in is impacting your food, you could move, or see how you could change that -- if you live near a corn or wheat farm, maybe start a community vegetable garden, or if you live in a cold place, figure out ways to preserve or store healthier foods for the winter.

For me, agreeing or disagreeing with the statement comes down to choosing between the active and the passive mindsets. I choose the former because to me, that’s the only path to constructive change.

Food Revolution

In the film we watched this week, Sadie and Safiyah talked to two administrators from the New York City Department of Education about school lunches and how the American diet -- basically, the policy environment -- has changed since post-WWI America.

Originally, after issues with malnutrition in soldiers, there was a focus on food that got you the calories you needed -- ‘mystery meat,’ some kind of vegetables, and bread, was the standard fare.Then, in the 1960s, the focus shifted away from nutrition to anti-hunger programs, which came alongside the rise of fast food, fatty foods, and carbohydrate-rich foods, the foods that are still a staple of the American diet today. Now, moving forward, there’s a movement for the balance of the two -- filling and nutritional, focusing on organic, low-fat, low-sodium, non-artificial foods.

The trend most surprising to me was how the American diet actually went downhill. The earlier diets were, out of necessity, healthy enough. It was when people were getting richer and people were finding ways to make food taste better, regardless of actual nutritional value, that the least healthy of the three examples of the American diet occurred.

In my family, as I said, we usually try to avoid the lingering influence of the second American diet. We rarely go to fast food places and tend to eat, as I mentioned previously, mostly quinoa-type grains or pasta, various vegetables, and chicken or fish. However, one thing we don’t monitor quite as much is the sodium or fat in our foods -- even though our homemade things won’t have the same extreme problems there packaged food often does, we still eat some of those and only sometimes get the low-fat or low-sodium version of things.

Later in the video, Sadie and Safiyah showed statistics about how obesity rates in America have steadily increased in America since the 1970s. This shows how all four food environments have changed since then -- individual taste preferences change when they realized everything seemed better fried or with high fructose corn syrup, social environments changed as everyone started getting into fast food and it became a quick and easy way to feed the family, policy environments changed as fast food was served as school lunch and fast food corporations gained the ear of the government, and even physical environments changed as fast food places spread and suddenly there was one just down the street… for everyone.

Why Bother?

This week in class I read an article called “Why Bother?” an opinion piece by New York Times author Michael Pollan about why (or why not) we should care about combating climate change on an individual level, and what we could do to do so (gardening). In class, we just finished a quarter on climate change and are beginning one on urban gardening, so this article was very relevant to our in-class article. Something I found very interesting in the article was the almost dystopian mindset of the author -- this idea of the market conditioning us to be helpless and inextricably interdependent definitely rang true in many ways, but seemed to present a problem or reality for which the only real solution would be to return to the post-Neolithic Revolution model for human civilization, and moderation or compromise weren't really presented as alternatives.

Too Late?

In the article, Pollan first outlined a very familiar mindset for the average citizen -- the idea that “no matter what we do, it will only be too little too late.” This is particularly for the individual; when people contemplate going completely green, they’re dissuaded by the knowledge that really, their biking to work every day is not going to have much impact on the large scale, and anyway, the vast majority of people are doing nothing, so why should they?

Image result for climate change disbelievers

There is also the thought that our inaction thus far has already led to negative feedback loops (warming leads to melting ice caps which leads to more warming, for example), increasing the rate of change so we are no longer able to do anything to stop this cycle of climate change.

However, I feel that the latter mindset is, to some extent, just an excuse not to do anything -- after all, how do we know we can’t stop it until we’ve tried? -- and that the former, while reasonable enough, ignores an important truth. Large scale change can only be made by many small-scale changes.

Because of this, yes, individual changes in lifestyle can create greater change. This is, in fact, the only way that greater change can happen. In fact, the issue of too-small scale may be solved by the power of behavioral chain reactions -- if enough people do it, it becomes the new normal. “No,” you might say, “if they make a law about it, then those other people might do it, not when they see me do it…” However, laws do not begin with politicians, they begin with a people’s movement of change -- therefore, for legalized change to happen, enough individuals must take personal initiative first.

What We Think vs. What We Can Do

Later in the article, Pollan quotes Wendell Berry’s statement about another main obstacle for mass action against climate change: “the split between what we think and what we do.” He’s referring to the phenomenon found in many people -- for example, they might support environmental organizations, but waste fossil fuels without a thought.

In many ways, this is a symptom of general lack of will to act. We know, in theory, that climate change is real and will have a major impact on the future, but can’t work up the motivation to actually make change in our everyday lives. Another example is food -- usually, people want to ‘eat healthily,’ and know that eating local and organic food will be better for both their body and the environment, but when it comes to paying more for organic foods or gardening themselves, they make excuses or “want to, but never get around to it.”

Cheap Energy Mindset

Another concept Berry comes up with is the idea of a “cheap energy mindset.” The cheap energy mind relies on market-based solutions, specialization, and consumerism. This mindset, as implied by the name, is made possible by cheap energy, specifically fossil fuels, because they allow us to specialize in one area of production and then delegate literally everything else to experts, as well as give monetary value to this specialize. This mindset has probably been what has allowed human civilization to reach where it is today, but Berry shows its downside.

Say, for example, you’re a dentist. Your contribution to society is an important one, and you protect people from the horrors of cavities and root canals. When you were in school, you left your education to your teachers. When you want to eat, you go to a grocery store, relying on agriculture and food companies. When you’re sick, you go to a doctor. All reasonable, right? After, it’s impossible for an individual to meet all their needs as well as a number of experts in each area can. That’s how human society functions, so of course, people are okay with it. And it’s only natural to pay experts for their work. So far, the cheap energy mindset works.

But what about politics and leadership? Should people be so caught up in the efficiency of this interdependence that they barely know what their representatives in government are doing, let alone making their voice heard in the system that creates laws for our entire country? Berry says no, and that this a huge reason that mass environmental change hasn’t happened. Basically, people are waiting for change in the form of policy and law from the government -- after all, we should leave politics to the politicians and lobbying for environmental protection to the environmentalists.

Urban Garden

The article concludes with a solution to the problems it brings up - gardening. In class, as well, we’ve discussed the urban gardening, with a video from Nourish: Food + Community. Both sources conclude that urban gardening is extremely beneficial, from the individual to global level. In fact, the article says “it’s one of the most powerful things an individual can do.”

A significant benefit of urban gardening is to the environment. Food you’ve grown yourself is the freshest and the most local food you can eat, which of course takes away from the carbon footprint of other, processed foods. Planting more plants means more carbon dioxide is taken from the air and replaced with oxygen. As well, time spent working in the garden is time not spent with fossil fuel-powered entertainment or other carbon footprint-increasing activities.

Another benefit is individual health and happiness. Gardening provides exercise and keeps you fit. It also, according to the Nourish video, fosters community by bringing neighbors, fellow gardeners, and even farmers together in backyards, community gardens, and farmer’s markets.

To President Trump: An Explanation of Climate Change

Image result for envelope with us flag stamp

This week in class, we pulled together what we've been learning all quarter -- bringing together temperature, density, air force, and weather to talk about climate change. Learning about climate change, naturally, made us want to do something about it. An important way we can make change is by letting our voice be heard by our representatives and leaders, so we wrote letters to the current president of the United States, the anti-climate change Donald Trump. Below is the letter I wrote:

President Trump,

You've already received a number of letters regarding your attitude towards climate change, I'm sure, and will receive many more. You stubbornly claim that the entire concept is a hoax, despite the fact that 97% of climate scientists agree that it exists; you just signed an executive order relaxing EPA restrictions, you've threatened to withdraw from the 2016 Paris Agreement -- anyone with a pencil, a brain, and some hope for our political system should demand that you at least attempt to see sense.

My letter, then will be one among many. You probably won't read it. If I'm lucky, I might get the attention of one of your secretaries. Nonetheless, I find it my duty, as one of the citizens of a country you have somehow been elected to lead, to teach you what I've been learning in my 8th grade science class, and demand that you take immediate action against human-caused climate change. Below, I explain why this would be in both your best interest, in language that you understand.

Trump, we have a problem. A tremendous problem. You like money, right? Good hard cash? Yeah, you do. Everyone knows it. And you, a billionaire, depend on the economy. Well let me tell you something. You know crops? People work to grow them, they sell them, people eat them, then corporations and billionaires make money? That's the agriculture industry. And then there's all the other places people work, like factories. You make money off of that too. Now, what if all those crops die? What if it gets too hot for people to work? All of a sudden, failed agriculture industry, factory slowdowns. Also, all the property you have in Florida, California. Sea level rises, there it goes. That's climate change. That's global warming. And it's a tremendous problem. Everyone's saying so.

And now, leaving behind the 4th grade vocabulary and selfish mindset you utilize so often, let me tell you why climate change matters to me. In Minnesota, we've been experiencing climate change firsthand, with the annual average temperature steadily increasing as well as extreme heat waves. This affects me and people in my community directly.

Just this winter, we've had a ridiculous amount of 60 °F days. This may not seem so bad, but if the rate of increase continues as it is, these warm winters will become uncomfortably hot, then uninhabitably so. And even this irregularity is having an effect on my community -- with the absence of the regular low temperatures that are the norm in Minnesota winters, people are often overdressed in unseasonably warm weather one day, then underdressed in more normal conditions the next. This is a long term trend -- 7/10 of the hottest recorded years have been within the past 15, and the state is warming at a rate of 0.5 °F per decade.

And not only is the annual average increasing, but so are the number of intense heat waves. Last summer, we had a heat wave bad enough that pools and libraries extended their hours so that people in the community whose homes don't have adequate air conditioning could be safe in weather hot enough to cause health problems, some of which, like strokes, can be fatal. If global warming is not checked, by the end of this century, extremely high temperatures that currently occur once every 20 years could occur as often as every two to four years, something which could have drastic consequences for the people in my state.

Oh, but silly me. I’ve been talking about the effects of climate change, but I forgot that denial is linked with ignorance, and that you probably don’t know what climate change is in the first place. Allow me to explain.

Let’s imagine a planet. We’ll call it Trumpland, so it captures your attention for more than thirty seconds. Trumpland is a spherical planet (Earth is too, in case you didn't know) snugly settled inside a mitten. This mitten is Trumpland’s atmosphere, and it keeps Trumpland warm because it’s partly made up of heat-trapping gases, which reflect some of the planet’s heat back towards it.

However, the humans living on Trumpland have been making some bad decisions. They burn fossil fuels for their energy, which releases carbon dioxide, a heat-trapping gas, into Trumpland’s mitten. The humans can’t be bothered to find other sources of energy, so the heat-trapping gases in the mitten build up.

Because more heat-trapping gases mean more heat reflected towards Trumpland and the humans keep releasing more and more carbon dioxide, their planet begins to heat up. Some of the smarter humans realize what is happening and try to stop it, but the rest remain ignorant, going so far as to elect a leader who pretends the effect is fake. Because of this, no measures are taken to prevent this climate change, and all the humans die when Trumpland becomes too hot and is ravaged by heat waves, storms, floods, droughts, and famine. The end.

And that, Trump, is what could happen here. ‘But wait-!’ you and your fellow climate change skeptics say. ‘The warming you’re talking about is really just caused by natural fluctuations in the Earth’s climate!” However, a number of credible scientific studies show that this is impossible. One of these, a 2013 Nature Geoscience study, proves that solar activity could not have contributed to more than 10% of the observed global warming over the 20th century. So no, it’s not “natural fluctuations.”

Of course, fluctuations are not the only way climate change skeptics explain away the increasingly dramatic signs of climate change making themselves evident. And, for each of their arguments, there are a far greater number of acclaimed scientists finding evidence that says the opposite. But consider this -- what if the skeptics ‘win’ and nothing is done, but climate change is real? Everything that happened to the fictional Trumpland and more would happen to Earth. What we now view as extreme weather events and natural disaster could become the norm, all because we did not address climate change when we should have. And if the skeptics are right? The only consequence would be the expense of implementing programs and energy sources far more sustainable and efficient than what we have now. The difference is pretty huge.

Even you must bring yourself to care about the fate of the entire planet. You have achieved a position you do not deserve and have already begun to abuse, but now that you have the power to do good, you must put aside the greed that seems to be your only motivation and act on an executive level to halt climate change.

You must acknowledge that climate change exists. You must uphold the 2016 Paris Agreement. You must reduce America’s carbon footprint and help America rely more on clean energy. You must act. And if you do so, you will not be the only one. Change is a collective mindset, and if everyone does their part in combating climate change, it will be overcome.

Sincerely,

Gitanjali Matthes

Cloud In A Bottle

This week, we read an article called "Cloud in a Bottle: High and Low Air Pressure." In class, we've been learning about air pressure and how it affects the weather. This article reinforced my learning by talking about how air pressure specifically plays a part in the formation of clouds, a connection I hadn't previously noticed. This made me want to learn more about clouds -- I'd like to spend time outside cloud-watching and identifying the different types.

Be The Molecule

Gas pressure is caused by the collisions of molecules or atoms with the walls of the container they are in. Pressure changes when either the volume of the container changes or the molecules' temperature changes. In the first case, the same amount of molecules are suddenly confined in a small space, so they collide with each other and the walls more often, creating more pressure. In the second case, the increased temperature makes the individual molecules move faster, so once again they collide with the walls more often and create more pressure.

When you fly in an airplane, you can feel the change of pressure in your ears when you ascend to higher altitudes. This is because the higher you are, the lower the air pressure, and the air trapped in your inner eardrum is suddenly high pressure in comparison. Because of this, it exerts pressure on your ear, causing the painful feeling that tells you you're high in the air.

In class this week we conducted an online pHet simulation, exploring the effects of heat, volume of container, and quantity on molecules. In the simulation, there was box with a lid, into which we could pump molecules. This box was re-sizable and could be heated or cooled. With these tools, my lab partner and I explored how many different ways we could blow the lid of the container -- increase the pressure in the box enough for that to occur.

We discovered three ways of doing this, two of which support my earlier statement that pressure increases when volume decreases or temperature increases. First, we pumped a single molecule into the box, then heated it up until it hit the lid so frequently that it was blown off. This shows that enough heat, on its own, can cause drastic changes in pressure. Second, we pumped in ten molecules, then made the box as small as possible. This made the molecules collide with the walls far more frequently, and showed that decreased volume can also cause major changes in pressure, Finally, we just pumped in huge amounts of molecules, which quickly caused the lid to be blown off. This last method didn't really support a separate way pressure increases, because it really just showed a larger scale version of decreased volume causing an increase in pressure,

Pressure Systems

Areas of high and low pressure are directly related to fronts. Fronts are where warm and cool air masses meet - when they meet, the warm air rises, leaving an area of low pressure below. These areas of low pressure are associated with clouds, precipitation, and storms, because the reduced weight of air above creates better conditions for these weather events to form.

Image result for us jet stream air pressure

Then, because high and low pressure areas are relative, not determined by number ranges, the areas without fronts are high pressure. In these high pressure areas, denser air is sinking, which mostly keeps clouds and precipitation from forming.

Areas of high and low pressure are also related to the jet stream. The jet stream separates areas of high and low pressure -- weaving around, it ducks south areas of low pressure and north of areas of high pressure. As well, the curve of the jet stream nearly matches the curves of isobars, which are lines that mark areas with the same air pressure.

This week, we discussed why, even though heat rises, the atmosphere is cold -- a statement which at first seems counter-intuitive. This is because, as heated molecules gain altitude they lose kinetic energy and cool down. This is also seen in the convection process -- molecules are heated from below and rise then eventually lose kinetic energy, and sink.

Cloud 101

Clouds form through a complicated process. First, there is water, perhaps a lake. Then, when the air is dry and warm, some water evaporates, or becomes vapor. If this vapor is warm enough, it rises, because it's less dense. Eventually, the vapor gets high enough and cools down, condensing and becoming the mass of water droplets we see as clouds in the sky.

Three things are necessary for this process -- low temperature, low pressure, and moisture in the air. Low temperature allows for the condensation process in the air. Low pressure allows for the initial rising of the water vapor, because when denser air is sinking, in high pressure areas, it makes it much harder for this to happen. Moisture, or water vapor in the air is obviously necessary, because without it there is nothing to undergo the process.

You cannot drown in a cloud. It's like fog -- the condensed water vapor isn't enough to suffocate you, and it's intermingled with air. If the water droplets were dense enough to drown you, they would be precipitation. So, don't worry if you're skydiving -- you won't drown on the way down.

Air Pressure

This week I read an article about air pressure and air force. In class, we’ve been exploring the same subjects through a series of experiments, so this article provided answers for many of the questions that came up during my exploration of the different ways air pressure works. Of course, the article also brought up even more questions — in particular, I was curious about the relationship between air pressure and the weight of air.

Air Pressure Demo

Two of the labs exploring air pressure were performed as a demonstration in front of the class. In the first demonstration, we placed a peeled, hard-boiled egg on the opening of a bottle in which there was a lit scrap of paper. I hypothesized that the egg would be sucked into the bottle, because the flame would consume the air inside the bottle. We observed the flame inside the bottle flicker and go out, and the egg squeeze through the neck of the bottle before falling with a pop and breaking on impact. My hypothesis was mostly correct, but incomplete — while I’d guessed what would happen, my ‘why’ wasn’t quite right. The egg wasn’t being sucked into the bottle, exactly, rather it was being pushed in by the higher air pressure outside the bottle. The reason that that higher air pressure existed because the flame had consumed the oxygen in the bottle, lowering the air pressure inside.

Image result for egg and bottle experiment

The second experiment was the same, only varying in that this time, the bottle was upside-down. I hypothesized that the same thing would happen as with the previous experiment, but that it would be slower this time because now air pressure would be fighting against gravity. This did end up happening — after a much longer period of time, the egg was pushed into the bottle with a slurp, because the flame inside had created an area of low air pressure.

These demonstrations served as proof for a number of properties of gases. First, we know that gases take up space, because before the flame consumed oxygen and the air pressure dropped, air was creating an equalized area of air pressure in the bottle, and was taking up space in a way that created the amusing reaction when absent. Secondly, we know that gases are compressible, because the compression is usually necessary to create the force exerted by the high pressure air on the egg in the two egg and bottle cases. Thirdly, we know that gases exert pressure, because it was air, a mix of gases, causing the pressure that pushed the egg into the bottle in both demonstrations.

I’ve been talking a lot about air pressure, but haven’t defined it — it’s the force exerted on a certain area by the mix of gases that make up air.

Air Pressure Labs

In class this week, we conducted a series of experiments exploring air pressure. Two experiments I found particularly interesting were “Ping Pong Funnel” and “Kissing Balloons.” Both of these were very simple, compared to the others, but still displayed the results of air pressure in an easily understandable manner.

Image result for ping pong funnel experiment

In “Ping Pong Funnel,” our task was simple — we were to place a ping pong ball in a funnel, then blow up the tube and try to push the ball into the air. I hypothesized that we would be able to blow the ball into the air, because we would create an area of pressure on the ball and cause it to hover in the air. However, my hypothesis was incorrect. We found no matter how hard we blew or how we held the funnel, the ball remained at the bottom of funnel. In reality, blowing up the tube caused the air touching the bottom of the ball to move faster, creating an area of lower pressure. This meant that the air around all the other parts of the ball was now by comparison higher pressure, exerting downward force on the ball and keeping it in the funnel.

“Kissing Balloons” was also about the connection between the movement of air and air pressure. In this experiment, we had two balloons attached to strings taped to opposite ends of the table. We then held them six inches apart, and I blew between them. I had hypothesized that my breath would, in my words, “push” the air out from between the balloons and they would come together to fill the space. As with my hypothesis regarding the first demonstration, I was right in my prediction but less so in my reasoning. The two balloons, after we blew hard between them, did sort of drift closer together, touch, then drift away. However, I once again thought more about the low pressure area “pulling” rather than the high pressure area “pushing.” Actually, since blowing between the two balloons caused an area of low pressure, the relatively high pressure around them pushed them together to create the “kissing” of the balloons.

I know air pressure exists because, even if it's unseen, it exerts force on many things around us. In both of the above experiments, I saw how areas of lower air pressure make us realize the impact of the higher, normal air pressure that is all around of us.

Air Pressure Reading

In the article we read this week, yet more evidence was presented that proves that gases exert pressure. First, there was the example of the tires that hold up our cars. As the article stated, “the pressure exerted by the air inside the tires is enough to hold up a car weighing 2000 pounds.” It’s not the rubber of the tires holding up those 2000 pounds - if that was the case, the tires would collapse and the car would be stuck a few inches off the ground. Rather it is the constant pushing of the air inside the tire outwards that provides the force necessary to hold the car. The second piece of evidence is the fact that you can’t blow up a balloon inside a bottle. If gasses couldn’t exert pressure, you would be able to blow it up, because the air trapped inside would offer no resistance. However, you can’t blow it up, so the air must exert pressure. Finally, when you place a crumpled piece of paper in a plastic cup and turn it upside down, submerging it in the water, the paper stays dry. This is because the air trapped inside the cup exerts pressure on the water, keeping it from touching the paper.

These examples - air pushing the walls of a tire, a paper cup, and bottle - all additionally show that gas molecules exert pressure on the walls of whatever container they are in. As well, in this week’s article, the author wrote that “gases exert pressure on every surface they come in contact with.” This is especially true when gases are trapped in containers, like tires, cups, or bottles.

Air pressure is caused by the weight of the air around us. While individual air molecules are very light, the collective mass of all the air molecules in our atmosphere pressing down becomes a force to be reckoned with. It doesn’t always feel like pressure to us, because we’re used to constantly feeling its weight, but it does exist, and as we saw with our experiments, can definitely affect our everyday life.

The Polar Vortex

This week I read an article about the polar vortex. In class, we’ve been conducting a number of labs concerning snow, rain, and the temperature, pressure, and density of air and water. The article relates to what we’re learning because the polar vortex is made possible by these factors, and to fully understand the vortex, you should understand the factors that allow for its existence as well. This article made me think about how the weather is in many ways just different reactions caused by interactions between a number of ‘building blocks’ that always stay the same, or maybe ingredients that can be mixed together in different ways to create different weather events.

Having A Meltdown

Snow and rain are both water, but are the same and different in many more ways than that. This week in class we conducted a lab called “Having A Meltdown,” in which we took the mass of 10, 15, and 20ml of water and snow and divided that by the volume to get the densities. I hypothesized that the water and snow would have the same volume, because there would be 200mL of each, but that the mass of each would be different - that the mass of the water would be greater, because it would be denser. After we calculated and averaged our findings, we concluded that the average density of water was 0.906 and the average density of snow was 0.733. Later, we learned that our results were off by a small margin, due to human error during the experiment. Using the correct values, we created a graph to represent that densities of snow, water, and ice -- around 0.5 for snow (because of the different types of snow, densities vary), 1.0 for water, and 0.92 for ice. You can then use the equation m = DV, a proportionality constant of the equation D = m/v, to use the density of different materials to calculate their mass or volume. For instance, if you wanted to calculate the mass of 200mLs of water vs. ice, you could create the equations m = 1(200) for water and m = 0.92(200) to compare the two. To contrast -- both snow and water are made up of H₂O, and are the same substance (water) undergoing phase changes. Their differences include their density, which affects the mass to volume ratio of each.

The Polar Vortex

An air mass is a body of air characterized by its uniform temperature, humidity, and pressure. The temperature just has to be uniform within the mass, not with the surrounding air, so you can have warm air masses and cold air masses. Warm air is less dense than cold air because, when warm, the air molecules spread farther apart, spreading the mass out and creating more volume. This means that warm air will rise above the denser cold air. In the article we read, it said that “The polar vortex is created because cold air takes up less space than warm air. Cold air above the arctic sinks, and new air rushes in to take its place.”’ In other words, when warm and cold air masses meet, the dance of rising and falling that occur can create a polar vortex. The article also explains that, odd though it may sound, the best polar vortex is a “strong and healthy” polar vortex. This is because a polar vortex is far less likely to ‘break apart’ and cause polar vortex events if it has a healthy flow, staying in line instead of sending random pieces of cold air down the jet stream.

Front and Center

Image result for hot and cold water density lab

Another experiment we performed in class was called Front and Center. In this experiment, we poured two 200mL cylinders of water into a divided container. One of the 200mLs was cold tap water and the other was hot enough that we could burn ourselves on the glass. In each cylinder, we added a drop of food coloring -- blue for the cold water, green for the warm -- to differentiate them. Once we had poured the two cylinders in their compartment, we removed the divider, causing an interesting and beautiful reaction. Before we performed the experiment, I had hypothesized that because the two temperatures would create two different densities, the water would separate, the cold water at the bottom and hot water on top. This hypothesis was correct - when the two masses of water touched, they mixed slightly at the edges, then do-si-doed, with the hot green water rising to the top and the blue water sinking to the bottom. Where they touched they transferred heat, creating a turquoise zone as well. This reaction occurred for the same reason I hypothesized it would -- when the water is warmer, the molecules push farther apart, making it less dense and therefore likely to rise above the denser cold water. Despite my hypothesis’ accuracy, performing and seeing the result of the experiment for myself was a fascinating experience, because the reaction was so distinct. In conclusion, when mixed, denser fluids will sink and less dense fluids will rise.

In conclusion, I learned a lot this week about density and phase changes, as well as about the polar vortex, thanks to the article we read. It will be very interesting to see how it all connects as part of the cosmic sandbox that creates weather.

Transfer Of Heat Podcast

This week, instead of writing a normal blog post, my classmate Sosina and I wrote and recorded a podcast about the transfer of heat, the difference between heat and temperature, and an experiment we conducted in class. Listen for more information and quite a few bad puns!

engineering information technology

Source of knowledge Engineering and information technology.

Pages