New Orleans, Louisiana
This is a placeholder blogpost. The article is to be written
Apps & Interactive graphics
Fortified But Still In Peril, New Orleans Braces for Its Future: In the years after Hurricane Katrina, over 350 miles of levees, flood walls, gates and pumps came to encircle greater New Orleans. Experts say that is not enough.
By John Schwartz and Mark Schleifstein, 2/24/2018
After a $14-Billion Upgrade, New Orleans’ Levees Are Sinking. Sea level rise and ground subsidence will render the flood barriers inadequate in just four years. By Thomas Frank, E&E News, Scientific American, 4/11,/2019
Rising Sea Levels May Limit New Orleans Adaptation Efforts. New Orleans sees that even modern engineering cannot eliminate flooding risk. By Emily Holden, ClimateWire on September 10, 2015. Scientific American.
Fortified but still in peril, New Orleans braces for its future: Our Drowning Coast. By Mark Schleifstein | Posted February 24, 2018.
Rising sea to displace 500,000 New Orleans area residents, study says; see where they might go. By Tristan Baurick, NOLA.com | The Times-Picayune. 4/20/2017.
A study published this week (April 2017) predicts that sea level rise will push hundreds of thousands of people out of U.S. coastal cities such as New Orleans. It says the population will boom in nearby inland cities such as Austin. The University of Georgia study is considered the first detailed look at how inland cities might be affected by sea level rise. It estimates more than than 500,000 people will flee the seven-parish New Orleans area by 2100 due to sea level rise and the problems that come with it, including frequent flooding and greater exposure to storm surges. That’s more than one third of metro New Orleans’s current population…. Across the United States, the study estimates, 13 million people will be displaced by sea level rise under a scenario in which some efforts are taken to mitigate the impacts of sea level rise. The biggest draw, it predicts, will be Austin, gaining 600,00 to 800,000 people on top of the metro area’s current estimated population of 2.1 million. Other inland cities likely to grow substantially include Orlando, Fla., Atlanta and Phoenix.
Migration induced by sea-level rise could reshape the US population landscape
Mathew E. Hauer. Nature Climate Change volume 7, pages 321–325 (2017)
Many sea-level rise (SLR) assessments focus on populations presently inhabiting vulnerable coastal communities, but to date no studies have attempted to model the destinations of these potentially displaced persons. With millions of potential future migrants in heavily populated coastal communities, SLR scholarship focusing solely on coastal communities characterizes SLR as primarily a coastal issue, obscuring the potential impacts in landlocked communities created by SLR-induced displacement. Here I address this issue by merging projected populations at risk of SLR with migration systems simulations to project future destinations of SLR migrants in the United States. I find that unmitigated SLR is expected to reshape the US population distribution, potentially stressing landlocked areas unprepared to accommodate this wave of coastal migrants—even after accounting for potential adaptation. These results provide the first glimpse of how climate change will reshape future population distributions and establish a new foundation for modelling potential migration destinations from climate stressors in an era of global environmental change.
The flipped classroom intentionally shifts instruction to a learner-centered model. Students take responsibility to learn the content at home, usually through video lessons prepared by the teacher or third parties, and readings from textbooks. In-class lessons include activity learning, homework problems, using manipulatives, doing labs, presentations, project-based learning, skill development, etc.
An early example of this was called Peer Instruction by Harvard Professor Eric Mazur, in the early 1990s.
Physlets (Physics apps, flash, JAVA, HTML5)
Any interactive computer simulations for teaching and learning physics, chemistry, math, and other sciences. They help make the visual and conceptual models of expert scientists accessible to students.
PhET Interactive Simulations
PhET are modern, refined Physlets. A suite of research-based interactive computer simulations for teaching and learning physics, chemistry, math, and other sciences. They are animated, interactive, and game-like environments where students learn through exploration. They emphasize the connections between real-life phenomena and the underlying science, and help make the visual and conceptual models of expert scientists accessible to students.
Teaching with Clickers/Classroom response systems
A classroom response system (sometimes called a personal response system, student response system, or audience response system) is a set of hardware and software that facilitates teaching activities such as the following.
- A teacher poses a multiple-choice question via an overhead or computer projector.
- Each student submits an answer to the question using a clicker.
- Software collects the answers and produces a bar chart showing how many students chose each of the answer choices.
- The teacher makes “on the fly” choices in response to the bar chart.
Ranking Task Exercises in Physics
Conceptual exercises that challenges readers to make comparative judgments about a set of variations on a particular physical situation. Exercises encourage readers to formulate their own ideas about the behavior of a physical system, correct any misconceptions they may have, and build a better conceptual foundation of physics.
Interactive Lecture Demonstrations (ILDs)
See Interactive Lecture Demonstrations, Active Learning in Introductory Physics, by David R. Sokoloff (Author), Ronald K. Thornton (Author)
Start with a scripted activity in a traditional lecture format. Because the activity causes students to confront their prior understanding of a core concept, students are ready to learn in a follow-up lecture. Interactive Lecture Demonstrations use three steps in which students:
Predict the outcome of the demonstration. Individually, and then with a partner, students explain to each other which of a set of possible outcomes is most likely to occur.
Experience the demonstration. Working in small groups, students conduct an experiment, take a survey, or work with data to determine whether their initial beliefs were confirmed (or not).
Reflect on the outcome. Students think about why they held their initial belief and in what ways the demonstration confirmed or contradicted this belief. After comparing these thoughts with other students, students individually prepare a written product on what was learned.
GIFs: Using short, step-by-step animations to help students visualize a complex process.
There are many scientific phenomenon traditionally taught with textbook and lecture. These have static diagrams, and for many students it is hard to visualize the process. As such, with GIFs specifically targeted to the idea or equation at hand, it becomes easier for students to grasp the essential ideas.
For instance, one can model an electric series circuit with two resistors with math, a circuit diagram, or a GIF. With the GIF we can see how the battery adds potential energy to the electrons in a circuit, while the electrons lose this potential energy as they go through any circuit element with resistance.
Rtotal = R1 + R2
V = I/R = I / Rtotal
Cooperative Group Problem-solving – Students work in groups using structured problem-solving strategy. In this way they can solve complex, context-rich problems which could be difficult for them to solve individually. This was developed by the University of Minnesota Physics Education Research Group.
Students in introductory physics courses typically begin to solve a problem by plunging into the algebraic and numerical solution — they search for and manipulate equations, plugging numbers into the equations until they find a combination that yields an answer (e.g. the plug-and-chug strategy). They seldom use their conceptual knowledge of physics to qualitatively analyze the problem situation, nor do they systematically plan a solution before they begin numerical and algebraic manipulations of equations. When they arrive at an answer, they are usually satisfied — they rarely check to see if the answer makes sense.
To help students integrate the conceptual and procedural aspects of problem solving so they could become better problem solvers, we introduced a structured, five-step problem solving strategy. However, we immediately encountered the following dilemma:
If the problems are simple enough to be solved moderately well using their novice strategy, then students see no reason to abandon this strategy — even if the structured problem-solving strategy works as well or better.
If the problems are complex enough so the novice strategy clearly fails, then students are initially unsuccessful at using the structured problem-solving strategy, so they revert back to their novice strategy.
To solve this dilemma, we (1) designed complex problems that discourage the use of plug-and-chug strategies, and (2) introduced cooperative group problem solving. Cooperative group problem solving has several advantages:
- The structured problem-solving strategy seems too long and complex to most students. Cooperative-group problem solving gives students a chance to practice the strategy until it becomes more natural.
- Groups can solve more complex problems than individuals, so students see the advantage of a logical problem-solving strategy early in the course.
- Each individual can practice the planning and monitoring skills they need to become good individual problem solvers.
- Students get practice developing and using the language of physics — “talking physics”.
- In their discussion with each other, students must deal with and resolve their misconceptions.
- In subsequent, whole-class discussions of the problems, students are less intimidated because they are not answering as an individual, but as a group.
Of course, there are several disadvantages of cooperative-group problem solving. Initially, many students do not like working in cooperative groups. They do not like exposing their “ignorance” to other students. Moreover, they have been trained to be competitive and work individually, so they lack collaborative skills.
Just-in-Time Teaching: Students answer questions online before class, promoting preparation for class and encouraging them to come to class with a “need to know.
Context-Rich Problems: Students work in small groups on short, realistic scenarios, giving them a plausible motivation to solve problems.
Open Source Physics Collection: Open source code libraries, tools, and compiled simulations.
Tutorials in Introductory Physics: Guided-inquiry worksheets for small groups in recitation section of intro calculus-based physics. Instructors engage groups in Socratic dialogue.
RealTime Physics: A series of introductory laboratory modules that use computer data acquisition tools to help students develop physics concepts and acquire lab skills.
Modeling Instruction – Instruction organized around active student construction of conceptual and mathematical models in an interactive learning community. Students engage with simple scenarios to build, test and apply the handful of scientific models that represent the content core of physics.
Force Concept Inventory – “The FCI is a test of conceputal understanding of Newtonian mechanics, developed from the late 1980s. It consists of 30 MCQ questions with 5 answer choices for each question and tests student understanding of conceptual understanding of velocity, acceleration and force. Many distracters in the test items embody commonsense beliefs about the nature of force and its effect on motion. ” Developed by Hestenes, Halloun, Wells, and Swackhamer (1985.) Sample question:
ASU Modeling Instruction
“The Drake Equation is a way to estimate the number of communicating advanced civilizations (N) inhabiting the Galaxy. It is named after Frank Drake who first summarized the things we need to know to answer the question, “how many of them are out there?” The equation breaks this big unknown, complex question into several smaller (hopefully manageable) parts. Once you know how to deal with each of the pieces, you can put them together to come up with a decent guess.”
(Text in this section adapted from “ATP synthase.” Wikipedia, The Free Encyclopedia. 27 Mar. 2019.)
ATP synthase is an enzyme that creates the energy storage molecule adenosine triphosphate (ATP). ATP is the most commonly used “energy currency” of cells for all organisms. It is formed from adenosine diphosphate (ADP) and inorganic phosphate (Pi).
The overall reaction catalyzed by ATP synthase is:
- ADP + Pi + H+out ⇌ ATP + H2O + H+in
The formation of ATP from ADP and Pi is energetically unfavorable and would normally proceed in the reverse direction.
In order to drive this reaction forward, ATP synthase couples ATP synthesis during cellular respiration to an electrochemical gradient created by the difference in proton (H+) concentration across the mitochondrial membrane in eukaryotes or the plasma membrane in bacteria
Molecular animation of ATP synthase
Biology, Chemistry, Simple machines
The search for extraterrestrial intelligence (SETI) is a collective term for any scientific searches for intelligent extraterrestrial life. It is primarily done by monitoring radio signals for signs of transmissions from civilizations on other planets.
What are radio waves?
Radio waves are just a part of the EM (electromagnetic) spectrum.
That sounds dandy, except, what exactly is the “electromagnetic spectrum”?
All parts of the EM spectrum – radio, visible light, etc. – are oscillating electric and magnetic fields. To learn the details, see Light is an electromagnetic field.
How are radio waves different from other parts of the EM spectrum?
They’re made of the same thing, behaving in exactly the same way. Only difference is that radio waves are hundreds of meters to thousands of meters long. Other parts of the spectrum have shorter waves.
What creates radio waves?
With a radio receiver we can hear radio waves coming from all around us. They are naturally produced, and comes from all over the Earth, and outer space. Radio waves are naturally created by:
* Wind whipping over a surface, creating static electricity
* atoms trapped in the magnetic fields around the Earth, and around all other planets as well.
* The Sun (puts out all frequencies of EM radiation!)
* All stars
* Ionized interstellar gas surrounding bright, hot stars
* There are even more complex radio waves naturally generated, you can read this paper: Natural and man-made terrestrial electromagnetic noise
By the late 1800’s humans had learned not only how to receive radio waves, but how to generate them. Today we artificially create radio waves for all sorts of purposes, including
Traditional, over-the-air, radio stations (AM and FM radio)
Traditional, old-fashioned, TV (television)
Cellphone communication (cell towers and the phones)
What is a radio telescope?
The technology of how we detect radio waves.
How does an antenna pick up radio waves?
“If we place a conducting material on the path of such a wave, the passing wave will create an oscillating electric field inside the material; and that field will accelerate charges back and forth through the conductor.”
History of SETI
This section has been adapted from “Search for extraterrestrial intelligence.” Wikipedia, The Free Encyclopedia. 4 Mar. 2019
There have been many earlier searches for extraterrestrial intelligence within the Solar System. In 1896, Nikola Tesla suggested that an extreme version of his wireless electrical transmission system could be used to contact beings on Mars. He conducted an experiment at his Colorado Springs experimental station.
In the early 1900s, Guglielmo Marconi, Lord Kelvin and David Peck Todd also stated their belief that radio could be used to contact Martians, with Marconi stating that his stations had also picked up potential Martian signals.
On August 21–23, 1924, Mars entered an opposition closer to Earth than at any time in the century before or the next 80 years. In the United States, a “National Radio Silence Day” was promoted during a 36-hour period from August 21–23, with all radios quiet for five minutes on the hour, every hour.
At the United States Naval Observatory, scientists used a radio receiver, miles above the ground in a dirigible, to listen for any potential radio messages from Mars.
A 1959 paper by Philip Morrison and Giuseppe Cocconi first pointed out the possibility of searching the microwave spectrum, and proposed frequencies and a set of initial targets.
In 1960, Cornell University astronomer Frank Drake performed the first modern SETI experiment, named “Project Ozma”, after the Queen of Oz in L. Frank Baum’s fantasy books. Drake used a radio telescope at Green Bank, West Virginia, to examine the stars Tau Ceti and Epsilon Eridani.
Soviet scientists took a strong interest in SETI during the 1960s and performed a number of searches. Soviet astronomer Iosif Shklovsky wrote the pioneering book in the field, Universe, Life, Intelligence (1962), which was expanded upon by American astronomer Carl Sagan as the best-selling book Intelligent Life in the Universe (1966).
In the March 1955 issue of Scientific American, John D. Kraus described an idea to scan the cosmos for natural radio signals using a radio telescope. Ohio State University soon created a SETI program.
In 1971, NASA funded a SETI study that involved Drake, Bernard M. Oliver of Hewlett-Packard Corporation, and others. The resulting report proposed the construction of an Earth-based radio telescope array with 1,500 dishes known as “Project Cyclops”. It was not built, but the report formed the basis of much SETI work that followed.
Why don’t any organisms detect radio waves?
(Honors Biology topic)
How difficult will this be?
It is very difficult to pick up Earth’s radio waves from another solar system. As such, we can imagine that it would very difficult to pick up radio waves here, from some other solar system. That’s why we aren’t really looking for random radio waves that happen to escape out into space. Rather, the current projects are looking for much more powerful signals, that we hope would be sent out on purpose.
“That’s a rather extraordinary claim, so I spoke to SETI expert and scifi novelist David Brin about it — and he’s not convinced detection is this easy. He told me that, even if an ETI had a one square kilometer array, they would have to point it a at Earth for the duration of an entire year. “Because it would take that long,” he told io9. “But why stare if you don’t already have a reason to suspect?”
Like SETI Institute’s Seth Shostak, Brin believes that Earth is not detectable beyond five light years. “With one exception: Narrow-focused, coherent (laser-like) planetary radars that are aimed to briefly scan the surfaces of asteroids and moons,” he says, “And not to be confused with military radars that disperse.””
How can we differentiate between natural or artificial (intelligent) signals?
Consider listening to the sound of radio static. Compare that to the sound of a song, or a person giving a speech. Both are sounds – how are they similar? How are they different?
Come up with ideas on how we could differentiate between natural or artificial (intelligent) signals.
“Humanity has received some odd signals in the past. We’ve also sent out some signals ourselves. How could we determine that a signal we’d received was artificial in origin? Or of course inversely, how could an extraterrestrial civilization determine a signal we had sent out was was artificial?”
Listening for Extraterrestrial Blah Blah: At the cosmic dinner party, intelligence is the loudest thing in the room. By Laurance R. Doyle, Illustrations by Tianhua Mao
The Water hole: What radio frequencies should we listen to?
Misconceptions about listening with radio telescopes
Radio signals diminish in strength very rapidly with distance – they decrease according to the inverse square law. What does that mean Consider cooking spray. Oil is sprayed through an opening. In this image, the cooking spray hits a piece of toast and deposits an even layer of butter, 1 mm thick.
When the butter gets twice as far, it becomes only 1/4 as this.
If it travels 3 times as far, it will spread out to cover 3 x 3,
or 9, pieces of toast.
So now the butter will only be 1/9th as thick.
(1/9 is the inverse square of 3)
This pattern is called an inverse-square law.
The same is true for a can of spray paint: as the paint travels further, it covers a wider area, so the paint per area is inversely less thick.
The same pattern of spreading out and weakening, the inverse square laws, is true for radio waves.
Animations of the inverse-square law – animated clip: Inverse-square law for light
Okay – so by the time that radio signals reach even the next solar system they would be unbelievably weak. The radio signals would be even millions of times weaker by the time they travelled across even 1% of the galaxy. Our radio telescopes could never pick up such radio signals.
So if that’s the case, what then are SETI researchers listening for?We are looking for a civilization that wants to be known, one that has deliberately built a high power radio beacon, aimed in one direction at a time. A tightly beamed signal would be millions of times stronger – if by chance we happen to be in its path.
Do SETI researchers believe that someone out there is deliberately sending a signal to us here on Earth specifically? No. However, we know that there are billions of stars, and tens of billions of planets. Many of these planets might support life. Therefore, at any given time there could be many thousands of other worlds with intelligent life
The hope is that some of them would want to communicate, sending a tight, beamed radio signal out into space. If so, then one day we might intercept such a communication.
Article: Is there anybody out there? Jason Davis, October 25, 2017, The Planetary Society
Goldilocks Zone/Circumstellar habitable zone
This section from evolution.berkeley.edu, A Place for Life: A special astronomy exhibit of Understanding Evolution
From the known properties of stars and of the chemistry of water, astronomers can define “habitable zones” around stars where liquid water (and hence life) could exist on the surface of planets.
Too close to the star, and water will boil; too far, and it will freeze. This so-called Goldilocks zone, where the temperature is just right, depends on both the distance from the star and the characteristics of the star itself.
The habitable zone around luminous giant stars is further from the star than the habitable zone around faint dwarfs.
Of course, as noted previously, life may also exist outside these zones, for example in subsurface oceans on icy moons heated from the moon’s interior.
We know that there are around 200 billion stars in our Galaxy. Recent research has revealed that most of them have planets, and that tens of billions of these planets are likely similar in size to Earth, made of rock, and orbit in their stars’ habitable zones.
The question that remains to be answered is what fraction of those potentially habitable worlds host life.
Habitable Zones of Different Stars. NASA/Kepler Mission/Dana Berry.
Habitable zones for binary star systems
What about planets in a solar system with two stars?
Most stars in the Galaxy have at least one stellar companion—binary or multiple star systems. Stars like our Sun with no stellar companion are in the minority.
It would probably be difficult for there to be stable, only slightly elliptical planet orbits in a binary or multiple star system.
Complex life (multi-cellular) will need to have a stable temperature regime to form so the planet orbit cannot be too eccentric. Simple life like bacteria might be able to withstand large temperature changes on a planet with a significantly elliptical orbit but complex life is the much more interesting case.
Suitable binary stars would be those systems where either:
(a) the binary stars orbit very close to each other with the planet(s) orbiting both of them at a large distance (called a “circumbinary planet”)
or (b) the binary stars orbit very far from each other so the planet(s) could reside in stable orbits near each of the stars—the one star’s gravity acting on a planet would be much stronger than that of the other star.
A cool article on this subject: I Built a Stable Planetary System with 416 Planets in the Habitable Zone
Strong magnetic fields may be necessary
Earth has a strong magnetic field. Turns out that this might be necessary on a planet if complex life is to evolve.
Why does Earth have such a strong magnetic field? Earth’s core is still hot and molten. Metal still moves inside it, and moving metal has moving free electrons. Electrons moving around – by definition – are an electrical current. And it turns out that electrical currents create their own magnetic field!
Inside the earth
This field protects the Earth’s atmosphere from some of the Sun’s radiation.
Without such a field most of a planet’s atmosphere is likely to be blown away into space, as happened to Mars.
Mars now has very little atmosphere, and its surface is constantly irradiated by solar radiation.
The Drake Equation
An equation named after Frank Drake, who first summarized the things we need to know to answer the question, “how many possible extraterrestrial civilizations are out there?” The equation breaks this complex question into several smaller (hopefully manageable) parts.
(for the entire SETI unit)
Common Core, English Language Arts Standards » Science & Technical Subjects
CCSS.ELA-LITERACY.RST.9-10.1 – Cite specific textual evidence to support analysis of science and technical texts, attending to the precise details of explanations or descriptions.
CCSS.ELA-LITERACY.RST.9-10.2 – Determine the central ideas or conclusions of a text; trace the text’s explanation or depiction of a complex process, phenomenon, or concept; provide an accurate summary of the text.
CCSS.ELA-LITERACY.RST.9-10.4 – Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context.
CCSS.ELA-LITERACY.RST.9-10.5 – Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy).
CCSS.ELA-LITERACY.RST.9-10.6 – Analyze the author’s purpose in providing an explanation, describing a procedure, or discussing an experiment in a text, defining the question the author seeks to address.
2016 Massachusetts Science and Technology/Engineering Curriculum Framework
HS-PS2-5. Provide evidence that an electric current can produce a magnetic field and that a changing magnetic field can produce an electric current.
6.MS-PS4-1. Use diagrams of a simple wave to explain that (a) a wave has a repeating pattern with a specific amplitude, frequency, and wavelength, and (b) the amplitude of a wave is related to the energy of the wave.
HS-PS4-1. Use mathematical representations to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling within various media. Recognize that electromagnetic waves can travel through empty space (without a medium) as compared to mechanical waves that require a medium.
HS-PS4-5. Communicate technical information about how some technological devices use the principles of wave behavior and wave interactions with matter to transmit and capture information and energy.
Next Generation Science Standards: Science & Engineering Practices
● Ask questions that arise from careful observation of phenomena, or unexpected results, to clarify and/or seek additional information.
● Ask questions that arise from examining models or a theory, to clarify and/or seek additional information and relationships.
● Ask questions to determine relationships, including quantitative relationships, between independent and dependent variables.
● Evaluate a question to determine if it is testable and relevant.
● Ask and/or evaluate questions that challenge the premise(s) of an argument, the interpretation of a data set, or the suitability of the design
Common Core Math Standards (Inverse-square law)
CCSS.Math.Content.7.RP.A.2a ( Grade 7 ): Decide whether two quantities are in a proportional relationship, e.g., by testing for equivalent ratios in a table or graphing on a coordinate plane and observing whether the graph is a straight line through the origin.
CCSS.Math.Content.7.RP.A.2c ( Grade 7 ): Represent proportional relationships by equations.
Star formation by collapse of molecular clouds: Computer simulation
“ collapse and fragmentation of a molecular cloud presented in “The Formation of Stars and Brown Dwarfs and the Truncation of Protoplanetary Discs in a Star Cluster” by Matthew R. Bate,”
How Stars Are Formed and Born, National Geographic
Birth of a Star | Out There | The New York Times
NASA/JWST | Planetary formation (HD)
The Life of a star, Dillon Gu
Boardgame – “Stellar Journey : The Game”, by Other Worlds Educational Enterprises
Formation of Black Holes
Black Holes Explained – From Birth to Death
Stephen Hawking explains black holes in 90 seconds – BBC News
Sound of Two Black Holes Colliding
Neil deGrasse Tyson Explains Wormholes and Black holes
This is from Staffan Qvist (@QvistStaffan)
co-author of A BRIGHT FUTURE (PublicAffairs Books 2019).
If the world built clean power as aggressively as Germany (normalized by the size of the economy), how quickly would the global electricity grid be “cleaned up”? Answer (see graph) is unfortunately not encouraging, even disregarding nuke phase-out.