GEOG 104 Lecture Notes - Lecture 2: Greenland Ice Sheet, Stock And Flow, System Dynamics

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nje1998

26 Jan 2022

School

Simon Fraser University

Department

Geography

Course

GEOG 104

Professor

Leanne Roderick

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Document Summary

Geog 104 - lecture 2: introduction to systems dynamics1. An interconnected set of elements that is conherently organized in a way that achieves something . Amount or quantity of a something residing in a particular place at a particular time. The rate at which stuff adds or subtracts from a stock. Apples picked per hour, water melted per month, fish born per year, knowledge lost per decade Geog 104 - lecture 2: introduction to systems dynamics2. Nasa satellite image of wildfire smoke, saturday sept 12, 2020. Geog 104 - lecture 2: introduction to systems dynamics3. Response to the change pushes the system farther in the same direction as the change. Response to the change counteracts the change stabilizing the system. Climate feedbacks both respond to ice sheet changes and, in turn, influence the ice sheet. Geog 104 - lecture 2: introduction to systems dynamics4. Geog 104 - lecture 2: introduction to systems dynamics5.

Related Questions

1. Convert the speed of Louisiana during the diurnal rotationofEarth, and its speed during the annual revolution of the Earthinm/s, km/s, Km/h, MPH. Make comparison to other known or hearof-speeds in this world, higher or slower.

Just flat out dont know how to do it need your help.

2. Give me 5 examples from you personal life of 5 differentsystemof reference you used to identify or describe motions. Nameandbriefly describe the system, and explain what you observed fromthatsystem of reference.

you can just give me a couple of examples so i'll at leastget thepoint. Thanks

An important question to consider when thinking about globalwarming is, "If the ice sheets near the poles melt, how much willthe sea level rise?" This seems like a difficult question, giventhe odd shapes of both the ice sheets and the oceans. But there aresome accurate approximations that allow the answer to be estimatedfairly accurately with reasonably simple calculations.

The critical idea is that both the thickness of the ice sheets andthe amounts of the sea-level rise are extremely small compared tothe radius of the earth. The radius of the earth is about 2/p x 107m -- more than 6000 kilometers. The ice sheet thicknesses we willbe concerned with are single digit miles and the sea level riseswill be in dozens of feet. As a result, in thinking about them, wecan essentially ignore the curvature of the earth. We can imaginepeeling the map of the earth off a globe and flattening it out (bymaking cuts, not by stretching it, so that we preserve the area).Then, both the ice and the sea level rise can be treated as right(not tilted) cylinders (though with funny shaped bases and tops).Since we know that the volume of a right cylinder is the area ofthe base times the height, we can easily estimate all the volumeswe need. A schematic picture of this approximation (with the heightof the ice mass greatly exaggerated -- you couldn't see it if Ididn't) is shown below. The error in these approximations is on theorder of the height of the cylinder considered divided by theradius of the earth; a very small number.
a. Assume that (after flattening the surface of the earth in ourimaginations) the ice sheet to be considered covers an area, A, andhas a thickness, d. The oceans currently cover about 75% of theearth's surface, and note that the surface area of a sphere is 4pr2where r is the radius of the sphere.

Generate an equation that will allow you to calculate h, the heightthe ocean levels will rise due to the melting of a an ice sheet interms of A, d, and r

b. As shown in the combined satellite photo on the right (fromGoogle Earth), Greenland is covered by a sheet of ice. This ice hasbeen measured to have a mean thickness of about 2 km. Recentobservations indicate that this ice sheet is beginning to retreat-- that it is melting at an accelerating rate.

Using the depth of the ice sheet and the scale given on thepicture, estimate how much sea level rise would be produced by themelting of the entire ice sheet lying on Greenland. (Note: You caneasily look this information up on the web. But the goal of thisproblem is in part to develop your estimation skills for thepurpose of building your ability to decide for yourself whether anygiven piece of information you find on the web is reasonable orbogus.)

(a) In air at 0°C, a 1.60-kg copper block at 0°C is set sliding at 2.50 m/s over a sheet of ice at 0°C. Friction brings the block to rest. Find the mass of the ice that melts.

(b) As the block slows down, identify its energy input Q, its change in internal energy , and the change in mechanical energy for the block–ice system.

(d) A 1.60-kg block of ice at 0°C is set sliding at 2.50 m/s over a sheet of copper at 0°C. Friction brings the block to rest. Find the mass of the ice that melts.

(e) Evaluate Q and for the block of ice as a system and for the block–ice system.

(f) Evaluate Q and for the metal sheet as a system.

(g) A thin, 1.60-kg slab of copper at 20°C is set sliding at 2.50 m/s over an identical stationary slab at the same temperature. Friction quickly stops the motion. Assuming no energy is transferred to the environment by heat, find the change in temperature of both objects.

(h) Evaluate Q and for the sliding slab and for the two-slab system.