What are the rates of change in earth systems?
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Scientists now use a systems view of Earth to understand the processes responsible for the evolution of the Earth on all timescales and the interaction of Earth's subsystems (atmosphere, biosphere, geosphere, hydrosphere). Understanding Earth means using a scientific approach that considers the Earth as a complex, evolving body, characterized by ceaseless change. It means understanding Earth on a global scale by describing how its component parts and their interactions have evolved, how they function, how they may be expected to evolve. \n\n\nWe are interested in how the Earth system functions, what is "normal," what causes change in the system, and how the system copes with change. The Earth system is sometimes compared to the human body. We are interested in how well our heart/ lungs/muscles/nerves, etc. work--but we are most keenly interested in how well the components work together--our overall health. So it is with Earth. \n\n\nDisturbances to the Earth system are called perturbations. They can encompass anything from a change in the amount of solar insolation reaching Earth to the amount of carbon dioxide humans are putting into the atmosphere. Any change that has an effect on the Earth system that is either amplified or damped is part of a feedback loop--either positive or negative. Positive feedback reinforces an action or response. For example, an increase of ice or snow in cold climates can encourage cooler temperatures and more ice and snow--a positive feedback. Negative feedback is usually more stabilizing and limits the deviation of the system. For example, if those cold climates had warmer temperatures, that would likely result in less ice and snow, which would encourage the continuation of warmer temperatures. Notice that positive feedback reinforces (amplifies) a behavior but does not mean that the behavior is desirable. See Daisyworld on page 9-13 for a more detailed look at systems.
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False. Scientists realize that radioactive decay happens at a steady rate which can be measured by radio-carbon dating. Through countless tests over many years, the consistent measurements so far have indicated that the Earth is about 4 billion years old.
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Currently, the earth's north magnetic pole moves about 40 kilometers per year.  The rate has varied considerably; it was only 10 km per year a century ago.
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4600 Formation of the approximately homogeneous solid Earth by planetesimal accretion  \n4300 Melting of the Earth due to radioactive and gravitational heating which leads to its differentiated interior structure as well as outgassing of molecules such as water, methane, ammonia, hydrogen, nitrogen, and carbon dioxide  \n4300 Atmospheric water is photodissociated by ultraviolet light to give oxygen atoms which are incorporated into an ozone layer and hydrogen molecules which escape into space  \n4000 Bombardment of the Earth by planetesimals stops  \n3800 The Earth's crust solidifies--formation of the oldest rocks found on Earth  \n3800 Condensation of atmospheric water into oceans  \n3500-2800 Prokaryotic cell organisms develop  \n3500-2800 Beginning of photosynthesis by blue-green algae which releases oxygen molecules into the atmosphere and steadily works to strengthen the ozone layer and change the Earth's chemically reducing atmosphere into a chemically oxidizing one  \n2400 Rise in the concentration of oxygen molecules stops the deposition of uraninites (since they are soluble when combined with oxygen) and starts the deposition of banded iron formations  \n2000 The Oklo natural fission reactor in Gabon goes into operation  \n1600 The last reserves of reduced iron are used up by the increasing atmospheric oxygen--last banded iron formations  \n1500 Eukaryotic cell organisms develop  \n1500-600 Rise of multicellular organisms  \n580-545 Fossils of Ediacaran organisms are made  \n545 Cambrian explosion of hard-bodied organisms  \n528-526 Fossilization of the Chengjiang site  \n517-515 Fossilization of the Burgess Shale  \n500-450 Rise of the fish--first vertebrates  \n430 Waxy coated algae begin to live on land  \n420 Millipedes have evolved--first land animals  \n375 The Appalachian mountains are formed via a plate tectonic collision between North America, Africa, and Europe  \n375 Appearance of primitive sharks  \n350-300 Rise of the amphibians  \n350 Primitive insects have evolved  \n350 Primitive ferns evolve--first plants with roots  \n300-200 Rise of the reptiles  \n300 Winged insects have evolved  \n280 Beetles and weevils have evolved  \n250 Permian period mass extinction  \n230 Roaches and termites have evolved  \n225 Modern ferns have evolved  \n225 Bees have evolved  \n200 Pangaea starts to break apart  \n200 Primitive crocodiles have evolved  \n200 Appearance of mammals  \n145 Archaeopteryx walks the Earth  \n136 Primitive kangaroos have evolved  \n100 Primitive cranes have evolved  \n90 Modern sharks have evolved  \n65 K-T Boundary--extinction of the dinosaurs and beginning of the reign of mammals  \n60 Rats, mice, and squirrels have evolved  \n60 Herons and storks have evolved  \n55 Rabbits and hares have evolved  \n50 Primitive monkeys have evolved  \n28 Koalas have evolved  \n20 Parrots and pigeons have evolved  \n20-12 The chimpanzee and hominid lines evolve  \n10-4 Ramapithecus exist  \n4 Development of hominid bipedalism  \n4-1 Australopithecus exist  \n3.5 The Australopithecus Lucy walks the Earth  \n2 Widespread use of stone tools  \n2-0.01 Most recent ice age  \n1.6-0.2 Homo erectus exist  \n1-0.5 Homo erectus tames fire  \n0.3 Geminga supernova explosion at a distance of roughly 60 pc--roughly as bright as the Moon \n0.2-0.03 Homo sapiens neanderthalensis exist  \n0.05-0 Homo sapiens sapiens exist  \n0.04-0.012 Homo sapiens sapiens enter Australia from southeastern Asia and North America from northeastern Asia  \n0.025-0.01 Most recent glaciation--an ice sheet covers much of the northern United States  \n0.02 Homo sapiens sapiens paint the Altamira Cave \n0.012 Homo sapiens sapiens have domesticated dogs in Kirkuk, Iraq  \n0.01 First permanent Homo sapiens sapiens settlements  \n0.01 Homo sapiens sapiens learn to use fire to cast copper and harden pottery  \n0.006 Writing is developed in Sumeria\n\n\nFor a Visual representation of all this go here:\nhttp://www.lpi.usra.edu/education/timeline/
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According to the US Geological Survey (USGS), the Earth is approximately 4.5 billion years old.\n\nThe articles below discuss the evidence for this estimate.
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rate of change=dy/dx=slope
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Four hours.  The earth rotates through a full 360 degree circle in 24 hours, this means it rotates at the rate of 15 degrees and hour (360 divided by 24).  So it will take 4 hours to rotate through 60 degrees.
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Actually, virtually the entire mass of the earth's surface has been through at least one cycle.\n \nMost scientists believe that the earth formed about 4.5 billion years ago. This is based on the dating of meteorites thought to have formed during the creation of solar system. \n\nThe oldest earth minerals that have been dated gives dates of about 4.4 billion years old--these are recycled zircons in some rocks from  Australia. The zircons are fragments of igneous rocks that were eroded and redeposited in sediments, which were cemented to form sedimentary rocks, (estimate 3.6-3.8 billion years ago) and then metamorphosed. (1) The Acasta Gneiss Complex near Great Slave Lake, Canada has been dated as  about 4.030 billion years.(2) Gneiss is a metamorphic rock (therefore--at least two/3 parts of the rock cycle represented here alone.\n\nIn fact, rocks as old as the earth do not cover the earth--they have been recycled:\nA. The ocean basins cover half the earth, and the basement rocks of the ocean basins are "relatively" young, not older than 180 million years old--formed as igneous rocks along spreading ridges--from recycled material. \nB. Continents cover the other half of the earth. If you look at geologic maps of the continents, you will see that only the cores of the continents are made of old Precambrian rocks. For example: here's a map that shows the location of Precambrian rocks in the conterminous United States. They make up only a small part of the States. All the rest of the rocks are younger. The Precambrian includes all the rocks older than about 544 million years--which includes mostly rocks way younger than the inferred 4.5 billion year age of the Earth. \n The following website shows a map of all the rocks-by-age at the surface of the conterminous United States: http://tapestry.usgs.gov/two/color.html. And the next url gives the legend for the map. http://tapestry.usgs.gov/ages/ages.html.
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If the mass of the earth changes, then if we could "weigh" it on a scale, its weight would change. Changing the mass of the earth definitely affects its rotation rate, and its orbit, as well as all the other orbits of bodies in the solar system, including the sun, and of course, bodies outside the solar system. \n\nAll of the laws of motion and gravity that the earth and the other bodies obey depend on the mass of the earth.\n\nHow might mass of the earth change?\n \n1. The earth is gaining mass every year from meteorites of course. The amount of material falling to earth is estimated to be between 37,000 and 78,000 tons per year (see first reference).\n\nI am not sure if this includes material from the solar wind, or from the tails of comets, or from cosmic dust (see below) which are also sources of material from space that the earth gathers, but I believe it does. \n\n\n2. The earth is also losing material because we are now launching satellites and sending space vehicles off on missions. \n\n3. At the boundary of the atmosphere and space (the exosphere) where air can escape into space. The amount of air that is lost depends on how fast the ions, atoms and molecules in the upper atmosphere are moving. I have including a web page that discusses this below. \n\n4. When radioactive material decays, it can emit electromagnetic radiation (gamma rays) that carry off a tiny amount of mass. Some of these gamma rays might make it all the way out of earth's atmosphere, but very few I would imagine. I am not sure how to estimate this. It would definitely have to be balanced against the flood of radiation that the earth is being bathed in by the sun and by cosmic rays. \n\nWithout doing any calculations, I would guess that the earth is probably experiencing a net gain of mass every year, and this increases the force of gravity between it and all the other celestial bodies. It also will make it spin more slowly, as the moment of inertia of the earth changes. However, the gain is very small. From the figures above, the earth's mass increases by roughly 10^(-15) per cent per year; that is, the earth experiences a gain of about 0.000000000000001 %  per year.
35095
Probably not. In my humble opinion, humans ultimately play a very insignificant role in the processes that shape this planet, when viewed from a geologic time-scale. After all, more than 90% of all species on this planet were extinct long before hominids evolved. The planet has experienced global warming much more extreme than the present warming trend, and forces such as plate tectonics and isostatic rebound are contributing to problems like the subsidence of the Louisiana coastline probably more so than man's changes in the drainage of the Mississippi River. There is evidence that the modern coastal subsidence of the US Gulf Coast is related to isostatic rebound from the glaciers melting in North America over 10,000 years ago. That is how slow many of these processes work. The climate of this planet has never been static, nor has the shape of the continents. Natural events like climate-changing volcanic eruptions, earthquakes (which build mountains that ultimately change weather patterns), catastrophic tsunamis, meteorite impacts, erosion, catastrophic floods, landslides, glaciation, all have much more impact on a geologic scale than man has done. Even catastrophic oil-spills occurred as a result of natural processes long before man built a supertanker. This planet might not even be habitable by humans if not for the warming effect of radioactive decay within the earth, and over geologic time, that will gradually decline. Light and heat from the sun is something we have no control over that will certainly change over time. Of course, none of this excuses man for damaging the planet with deforestation, greenhouse gases, habitat destruction, etc., but we all need to recognize that even our best efforts may not affect the long-term changes that are taking place around us almost unseen due to the slow progress of these changes. We are going to have to work at not becoming just another part of the fossil record and our ability to adapt to climate change is probably the only thing that will allow the human race to survive long-term. This is just the opinion of this geologist.
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The worst thing that'll hurt the Earth is getting melted by the Sun when it grows from a small yellow star into a red giant star in about seven billion years, as estimated by astrophysical calculations.\n\nThe Sun will  transform all the hydrogen it has into helium by fusion of hydrogen nuclei into helium nuclei. The helium will accumulate in the Sun's nucleus, and the Sun's volume will increase. Its temperature will also increase. As a consequence, In about three billion years, water in the Earth's oceans will evaporate. In about seven billion years, the Sun will ultimately swallow Mercury, and its temperature will be so high that the Earth's rocks will melt.\n\nAfter that, the Sun will have burned all the helium in it and shrink into a white dwarf star, so the Solar System, including the Earth, will freeze.\n\nThat will mark the end of the Earth, and so it will be the thing that will hurt it most.
655853
Precession! The shape of Earth’s orbit becomes more or less oval (eccentricity), Earth wobbles as it spins (precession), and Earth's axis changes too (tilt). All these changes, over thousands of years, causes Earth's climate to change.
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Hint: The Earth revolves 7.5 degrees every 30 minutes.
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Earth is rotating at a speed of about 1100 miles per hour. If our planet suddenly stopped rotating, the atmosphere would still be in motion at that speed. The atmosphere would be moving so fast it would literally sweep the land masses clear of anything not anchored to bedrock, this would mean rocks, soil, trees, buildings, people and animals. All would be swept up into the atmosphere.
199932
The earth's rotation.
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Well the sun is getting hotter and will continue to do so until most of  the hydrogen is converted to helium it will then expand to become a red giant. \n\nHowever the effects of this will be minute compared to processes on the earth, IE its tilt, orbit, and mankind's carbon emissions and of cause the deforestation. It must be remembered that we are in an interglacial period and the earth has been a lot warmer than it currently is. The problem is that the increase in temperature is the largest in thousands of years. BUT, when the last ice age finished the temperature rise in approx 50 years was much higher than our rise in 200 years so it is all relative.\n\nThe "freak" weather conditions on other planets may well be perfectly normal for them, remember at best we have only had probes in regular orbits around the other planets for at best 20 years with the resolution capacity to take images that show them.\n\nThe biggest problem is that although in UK we have large taxes on fuel much bigger than any proposed tax by most over governments, there is no unified effort to get us off fossil fuels, if there was someway of getting me out of my 1.2 litre small car than fine, But whats the point when someone in an other country with a 4 litre car still pays less than me to go the same distance?
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the earth is about 4.5 billion years old