Score
Title
98
AskScience Panel of Scientists XVIII
550
AskScience AMA Series: I am Melinda Krahenbuhl and I am the director of the Reed Research Reactor, the only nuclear reactor operated primarily by undergraduate students. AMA!
8468
What elements are at genuine risk of running out and what are the implications of them running out?
269
Can you break sound barrier under water or any other material?
4021
What’s the largest star system in number of planets?
19
Why does plastic turn white at the creases when folded/bent?
3
How does thermal imaging work?
21
Do microwaves leave residual changes to molecules after heating?
4
Can a setup of hall engines provide enough thrust to keep a satellite stationary above earth?
2
Does the temperature have any (noticable) effect on air resistance?
6
How does a memristor work?
1
How does radiation poisoning work?
1
How is the height of the mountain measured?
3827
What is the effect, positive or negative, of receiving multiple immunizations at the same time; such as when the military goes through "shot lines" to receive all deployment related vaccines?
4
If a planet had a radius that was equal to the altitude of Earth’s geosynchronous orbit, but had the same mass and rotational period as the Earth now, would there be reduced or zero gravity on the surface?
1
What is lost and what is preserved in a particle collider?
8
Why does snow melt in the sunlight, even when the temperature outside is below freezing?
11
Mar's summer temperature can be 20 celsius. Could a human survive with just an oxygen mask?
2
Is there an altitude at which there is no longer a speed of sound?
0
How would a moving target affect the rate of nuclear fission vs a stationary target?
14
What would a spaceship moving at 0.9c firing lasers both in front of it and behind it look like to an external reference frame?
6
Does adiabatic warming occur when air descends in the Earth's polar cells?
24
How does the cosmic microwave background persist? Why hasn't it been distorted and destroyed by new sources of energy pumping into space?
6
How does cancer metastasis work?
7
Can a comet maintain an atmosphere?
1
How does RFID blocking material work?
0
Does the Meissner effect relate to Lenzs law?
9
Why hasn't The Asteroid Belt formed a planet?
10
Can you use a normal (CMOS) camera for detecting scintillation?
3
How do people know that the Island of Stability exists? And could there possibly be another "island" after it?
59
How can brain cells cause tumours even though they can not multiply?
7
How far back can you go before carbon dating becomes unreliable?
2
How does a computer process “simple” events?
1578
Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology
3
What is the nonrenewable fuel cost to produce x quantity of electricity?
1132
What triggers beta particles to form, and for what reason can they not penetrate substantially thick aluminium?
0
What is the strongest a magnet could be?
1242
If capacitance increases as distance between plates decreases, why aren't there very small 1F capacitors?
0
What makes astronomers think life in general isn't possible on gas giants?
1
How applicable are Newtonian Physics in real life? Is it completely false or are there some concepts which can be used to accurately predict real-life situations?
1050
is it possible to move an object in circular motion using magnets?
4
What would hydrogen in metal form look like?
917 chthonicutie TL;DR yes, but not by virtue of superoceans themselves. I am not sure of the effects of supercontinents on their own, but I can answer this question in the context of Earth's history, specifically the end [Permian](https://en.wikipedia.org/wiki/Permian) mass extinction event, which took place in the time of Pangaea. I am a graduate student in geology and currently studying mass extinction events. /u/Neolavitz is right in that the biggest limiting factor for tropical storm growth is ocean water temperature. To elaborate... When certain conditions are met, the oceans can become very warm. One such warming event (called a Hothouse state) took place at the end of the Permian, when the [Great Dying](https://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event) occurred. It is thought that this Hothouse state was triggered by a massive eruption at the [Siberian Traps](https://en.wikipedia.org/wiki/Siberian_Traps), which released enormous amounts of CO2 and other nasty compounds onto the surface of the planet. One of the consequences of this was dramatically slowed ocean circulation in a haline mode. A haline mode "generates warm saline bottom water that heats the ocean" (166), which transfers heat from the equator to the poles. This is in contrast to our present cycle, where deep ocean currents transport cold water to low latitudes, creating a gradient of heat and overall cooler oceans worldwide. In the Hothouse state, cyclones, which are restricted to about 40 degrees of latitude N or S in our current climatic regime, may traverse the entire globe (90N and 90S) thanks to worldwide elevated ocean temperatures. They would also create a positive feedback situation: > As storms reached to higher latitudes, they would help deliver more heat to those regions. That would, in turn, further warm higher latitude surface waters, making it more likely that subsequent storms would have an ever-greater poleward reach. Polar storms would also lead to increased polar cloudiness, which would impede surface heat radiation to space, thus warming the poles even more. Magntitude of storms would increase. Modern cyclones are limited in their size by colder, deeper waters. The bases of their waves reach the colder deep waters and lose heat and energy. In a warmed ocean, this restraint would no longer exist. Kidder and Worsley specifically say, "the cyclone-magnitude governor would be **completely removed** in a Hothouse..." (emphasis mine). So to answer your third question, no, there are theoretically no limiting factors in a very warm, humid situation. To answer your fourth question, the vast, dry deserts of Pangaea were the most likely stopping zones for these storms, as they would be deprived of moisture in the deserts. Source: > Kidder, D.L., and Worsley, T.R., 2010, Phanerozoic Large Igneous Provinces (LIPs), HEATT (Haline Euxinic Acidic Thermal Transgression) episodes, and mass extinctions: Paleogeography, Paleoclimatology, Paleoecology, v. 295, p.162-191.
389 [deleted] [removed]
1552 Neolavitz My understanding is that there were what are known as hypercanes. These theoretic storms would require an ocean temperature around 120° f and would produce Mach .6 winds. I'm not aware of if they actually happened though during our Pangaea era they likely did hope this helps op. I guess I'll add in some more info. Hurricanes need warm water to grow theoretically there is little to no known limit to how powerful they can become just depends on how long they have been at sea and the ocean temperature at that time. General consensus is a hurricane becomes a hyper cane at Sub 700mbar pressure or around 400mph sustained wind. The conditions for this to happen would be around 120 + ° ocean temps deeper than 100 meters and little to no windsheer or land impact. Some additional info for everyone the 700 mbar number and 400mph winds are just the scientific community consensus at this point it could be weaker or stronger to be classified as a hypercane i personally would say anything under 800mbar and 300 mph winds would qualify putting needed ocean temp at around 108° f Edit: on phone autocorrection Edit 2: a sauce for those interested https://en.m.wikipedia.org/wiki/Hypercane Edit 3: sauce for anyone interested in global warming affect on hurricanes and man vs nature global warming. https://www.gfdl.noaa.gov/global-warming-and-hurricanes/ Edit4: for the rest of the world 50°c is 120°f and 400mph is 640kph sorry I forgot to include you guys
75 [deleted] Unrelated to superoceans per se, but I have read a theory about 'hypercanes' proposed by a professor from MIT named Kerry Emanuel. Any analysis of that is beyond me as a layperson, but I believe the full text of his paper is available online if anyone was interested in confirming how reasonable or unlikely his ideas might be. EDIT: Here's a link to the paper for those interested! [Tropical Cyclones - Kerry Emanuel](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwiAnIOpoJvWAhUk5IMKHdw1DGYQFgg0MAI&url=ftp%3A%2F%2Ftexmex.mit.edu%2Fpub%2Femanuel%2FPAPERS%2Fannrevfinal.pdf&usg=AFQjCNHd1Xo28shD96bUX5CIDvl89Qv2nQ)
922 0 chthonicutie TL;DR yes, but not by virtue of superoceans themselves. I am not sure of the effects of supercontinents on their own, but I can answer this question in the context of Earth's history, specifically the end [Permian](https://en.wikipedia.org/wiki/Permian) mass extinction event, which took place in the time of Pangaea. I am a graduate student in geology and currently studying mass extinction events. /u/Neolavitz is right in that the biggest limiting factor for tropical storm growth is ocean water temperature. To elaborate... When certain conditions are met, the oceans can become very warm. One such warming event (called a Hothouse state) took place at the end of the Permian, when the [Great Dying](https://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event) occurred. It is thought that this Hothouse state was triggered by a massive eruption at the [Siberian Traps](https://en.wikipedia.org/wiki/Siberian_Traps), which released enormous amounts of CO2 and other nasty compounds onto the surface of the planet. One of the consequences of this was dramatically slowed ocean circulation in a haline mode. A haline mode "generates warm saline bottom water that heats the ocean" (166), which transfers heat from the equator to the poles. This is in contrast to our present cycle, where deep ocean currents transport cold water to low latitudes, creating a gradient of heat and overall cooler oceans worldwide. In the Hothouse state, cyclones, which are restricted to about 40 degrees of latitude N or S in our current climatic regime, may traverse the entire globe (90N and 90S) thanks to worldwide elevated ocean temperatures. They would also create a positive feedback situation: > As storms reached to higher latitudes, they would help deliver more heat to those regions. That would, in turn, further warm higher latitude surface waters, making it more likely that subsequent storms would have an ever-greater poleward reach. Polar storms would also lead to increased polar cloudiness, which would impede surface heat radiation to space, thus warming the poles even more. Magntitude of storms would increase. Modern cyclones are limited in their size by colder, deeper waters. The bases of their waves reach the colder deep waters and lose heat and energy. In a warmed ocean, this restraint would no longer exist. Kidder and Worsley specifically say, "the cyclone-magnitude governor would be **completely removed** in a Hothouse..." (emphasis mine). So to answer your third question, no, there are theoretically no limiting factors in a very warm, humid situation. To answer your fourth question, the vast, dry deserts of Pangaea were the most likely stopping zones for these storms, as they would be deprived of moisture in the deserts. Source: > Kidder, D.L., and Worsley, T.R., 2010, Phanerozoic Large Igneous Provinces (LIPs), HEATT (Haline Euxinic Acidic Thermal Transgression) episodes, and mass extinctions: Paleogeography, Paleoclimatology, Paleoecology, v. 295, p.162-191.
390 0 [deleted] [removed]
1549 0 Neolavitz My understanding is that there were what are known as hypercanes. These theoretic storms would require an ocean temperature around 120° f and would produce Mach .6 winds. I'm not aware of if they actually happened though during our Pangaea era they likely did hope this helps op. I guess I'll add in some more info. Hurricanes need warm water to grow theoretically there is little to no known limit to how powerful they can become just depends on how long they have been at sea and the ocean temperature at that time. General consensus is a hurricane becomes a hyper cane at Sub 700mbar pressure or around 400mph sustained wind. The conditions for this to happen would be around 120 + ° ocean temps deeper than 100 meters and little to no windsheer or land impact. Some additional info for everyone the 700 mbar number and 400mph winds are just the scientific community consensus at this point it could be weaker or stronger to be classified as a hypercane i personally would say anything under 800mbar and 300 mph winds would qualify putting needed ocean temp at around 108° f Edit: on phone autocorrection Edit 2: a sauce for those interested https://en.m.wikipedia.org/wiki/Hypercane Edit 3: sauce for anyone interested in global warming affect on hurricanes and man vs nature global warming. https://www.gfdl.noaa.gov/global-warming-and-hurricanes/ Edit4: for the rest of the world 50°c is 120°f and 400mph is 640kph sorry I forgot to include you guys
74 0 [deleted] Unrelated to superoceans per se, but I have read a theory about 'hypercanes' proposed by a professor from MIT named Kerry Emanuel. Any analysis of that is beyond me as a layperson, but I believe the full text of his paper is available online if anyone was interested in confirming how reasonable or unlikely his ideas might be. EDIT: Here's a link to the paper for those interested! [Tropical Cyclones - Kerry Emanuel](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&uact=8&ved=0ahUKEwiAnIOpoJvWAhUk5IMKHdw1DGYQFgg0MAI&url=ftp%3A%2F%2Ftexmex.mit.edu%2Fpub%2Femanuel%2FPAPERS%2Fannrevfinal.pdf&usg=AFQjCNHd1Xo28shD96bUX5CIDvl89Qv2nQ)