is the sun radiating more energy (heat) now than in the last century?
156733
Sun has a nuclear reaction (fission of Hydrogen gas)to radiate energy. Theoratically as much as Hydrogen is being used in the process of energy production the net quantity of hydrogen is being reduced and so net amount of reacting atoms is decreasing. Thus energy of sun is being reduced. However, the rate of decrease in the active mass is so slow that it can not be measured in course of few centuries.\n\nThe much referred worming of air or global worming, as replied here by one other, is due to increasing pollution of air or green effect.
475816
I actually did hear about that in my college Astronomy class. I think it's pretty awesome. I mean, what if our sun burnt out. Maybe we could still have a significant amount of solar energy and radiation that could help us survive. I'm not sure if the star is old enough to develop life or not. It could have already developed it, and we just have no knowledge of it.
960490
CO2 is 30% higher than it has been for 650,000 years. Methane is 130% greater. These are two of the main pollutants humans put into the atmosphere in excess, and they are two of the primary greenhouse gases.\n\nLook at the 'hockeystick', which shows a dramatic warming since 1950 after a fairly stable climate for 1000 years. In fact, the 10 hottest years in recorded history have all happened since 1990, with 2005 being the hottest, and 2006 is shaping up to maybe break that record.\n(see links below)\n\nHow's that for proof of man's fault in this? There is ample proof, any real scientist will tell you that.\n\nThere has NEVER been an article doubting man's influence on global warming published in a peer-reviewed journal. A recent study of almost 1000 proved that.\n\nYes, the earth naturally heats and cools, but the rate and amount we are warming now is unprecedented in the recent geologic past. We are doing this, and we must stop it. This is not some political statement or rhetoric. This is science trying to educate a crass, ignorant public of the damage they are doing. The magnitude of temperature increase ALREADY is about 10x that of the 'little ice age' of the middle ages, and rate and amount are only going up. \n\nJust to be clear, glacial and interglacial cycles are mainly controlled by astronomical fluctuations, but we have a detailed record of the last 7 cycles, and what the climate and CO2 is doing now is way different and extreme. The rate of increase is much higher than in the past AND the value itself is much higher.\n\nHI CO2: \nhttp://news.bbc.co.uk/1/hi/sci/tech/4467420.stm\nHOCKEY STICK: \nhttp://news.bbc.co.uk/1/hi/sci/tech/5109188.stm\nGeneral climate stuff: \nhttp://news.bbc.co.uk/1/hi/sci/tech/3897061.stm
168576
- The Sun is so large, you could fit over one million Earths inside it.\n- The Sun consumes four million tons of hydrogen every second. Even so, it's so vast that our star has enough fuel to keep it shining for another five billion years.\n- The Sun's energy output is estimated to be 386 billion, billion megawatts. So in 15 minutes our Sun radiates as much energy as mankind consumes in all forms, during an entire year.\n\n- The sun is fascinating ! :)
731384
The sun does go through an eleven year cycle where sunspots and electromagnetic storm activity peaks every 11 years or so.  I don't know if it's getting stronger every time, though.  It does affect mankind more every cycle, but thats because we have more and more satellites in orbit all the time, so there's more hardware to be affected.  It won't cause too much trouble on the ground, though.  The Van Allen radiation belts and the ozone layers block most of it.  Mostly it would affect communications, and cause radio static, etc.  I wouldn't get your knickers in a knot over it.
329960
Solar energy was popular in the last oil crisis in the 70's.  But then over time, gas got cheap and cars burned leaner and then we became complacent.  Solar energy became a political thing, and it lost popularity.  \n\nSocieties do not change unless they are forced to adjust to changing economic climates.  I think people in this country will start seeking that change as heating bills stays over 600 a month and gas sells for over 5 bucks a gallon.  Then you'll see real change...
515649
http://www.darvill.clara.net/altenerg/solar.htm\n\nThis is a favorite source of future energy for many people, comforted by the thought that it is unlimited. But, quite the contrary is true. The Sun will exist for a long time, but at any given place on the Earth's surface the amount of sunlight received is limited--only so much is received. And at night, or with overcast skies, or in high latitudes where winter days are short and for months there may be no daylight at all, the sunlight received is very limited at times. Direct conversion of sunlight to electricity by solar cells is a promising field, but the amount of electricity that can be generated by that method is not great compared with demand. The conversion efficiency is low, about 12 percent with present technology.\n\nSolar energy in quantity requires huge installations. It has been estimated that an area of 60 square miles in relatively clear central Oregon would have to be covered with solar cells in order to meet the present electric needs of that State. About 10% of the cells have to be replaced each year. But the big problem is how to store significant amounts of electricity when the Sun is not available to produce it. That problem remains unsolved. The statement that "solar energy will not make next century's electricity" is probably right. And the end product is electricity--a very limited replacement for oil.
845575
Well, the solar energy received by Earth is considered a constant. The heat from residual internal sources is considered to be minimal compared to the amount received by the Sun. Also the idea of a constant temperature is relative to the scale of time and space you choose. I'm not going into variations possibly due to sunspot occurrence, orbital, precession, axis wobble, volcanic, meteor impacts, nor seasonal changes.\nHere is a general model of energy transfers, heating and temperature.\nThe amount and wavelength of energy absorbed by a substance or blackbody causes it to heat to a particular temperature and radiate at a particular wavelength. Though the atmosphere is of a layered, mostly permanent composition and the Earth surface is not contiguous, this helps understand the effect of radiant energy on Earth. The reactions of the Sun make it so hot the radiant energy is essentially short wave (high frequency). Consider 100 units of solar sw received by the Earth (insolation), the atmosphere absorbs 25 (mostly due to ozone in the stratosphere) and reflects or scatters 25, while the water/terrain at the surface absorbs 45 and reflects 5. As the terrain and atmospheric gases absorb the sw energy they heat, but not too hot, and radiate long wave energy (low frequency).\nThe Earth surface radiates 104 units of lw - 100 to the atm and 4 out to space. The atm radiates 154 units - 88 back to Earth and 66 out to space. How can this happen and where does the additional energy come from?\nThere are several parts of this development.\nPart of the reason is the atm is a layered, mostly gaseous composition that exchanges energy amongst the layers, the Earth surface, and out to space. Another part is the other ways energy is transferred, such as the convection and turbulent flow of gases that transfer latent and sensible heat between the surface and atmosphere. You experience this when water is transported and goes through its various phases to develop the local weather.\nLets give these processes values. Convective processes values account for 22 units of latent heat and 7 of sensible heat.\nNow tally the total energy absorbed by the surface as 45 + 88 = 133 and the atm as 100 + 25 = 125. The convective processes ensure the energy balance by transferring 29 units of energy from the surface to the atm to obtain the 104 units and 154 units mentioned earlier. This leads to development of a mean global temperature as we know it at 15 deg C.\nNotice how much the atm is relied upon to transfer energy out to space? Changing the atm composition with additional variable/ long term gases, particulates, and aerosols can alter the events.\nParticulates and some gases can cause more reflection at the top of the atm resulting in less insolation, less heating, and lower temperature. Addition of some gases into the atm can increase the absorbtion of lw radiation or prevent it from being transferred to space. When it comes back to the surface, additional heating and a temperature increase will result if the convective processes cannot adjust for the increased energy.
664935
NO because of all the new cars and fossil fuel that people are burning. because of that the hi concentration of Co2 in the atmosphere Will result in global warming. In the last 100 years the global temperature has GROWN by 1 degree Celsius. and in the next 50 years or so the temperature Will rise by another 3 degrees resulting in freak weather.
737812
Both Jupiter and Saturn radiate more energy than they receive from the sun
575202
heat is a form of energy.
456954
Ok here ya go!\n\n In 2005, worldwide capacity of wind-powered generators was 58,982 MW, their production making up less than 1% of world-wide electricity use. Although still a relatively minor source of electricity for most countries, wind power generation more than quadrupled between 1999 and 2005.\n\nMost modern wind power is generated in the form of electricity by converting the rotation of turbine blades into electrical current by means of an electrical generator. In windmills (a much older technology) wind energy is used to turn mechanical machinery to do physical work, like crushing grain or pumping water.\n\nWind power is used in large scale wind farms for national electrical grids as well as in small individual turbines for providing electricity in isolated locations.\n\nWind energy is abundant, inexhaustible, widely distributed, clean, and mitigates the greenhouse effect.\n\nAn estimated 1 to 3 % of energy from the Sun that hits the earth is converted into wind energy. This is about 50 to 100 times more energy than is converted into biomass by all the plants on earth through photosynthesis. Most of this wind energy can be found at high altitudes where continuous wind speeds of over 160 km/h (100 mph) occur. Eventually, the wind energy is converted through friction into diffuse heat all through the earth's surface and atmosphere.\n\nThe origin of wind is simple. The earth is unevenly heated by the sun resulting in the poles receiving less energy from the sun than the equator does. Also the dry land heats up (and cools down) more quickly than the seas do. The differential heating powers a global atmospheric convection system reaching from the earth's surface to the stratosphere which acts as a virtual ceiling.\n\nThe change of seasons, change of day and night, the Coriolis effect, the irregular albedo (reflectivity) of land and water, humidity, and the friction of wind over different terrain are some of the factors which complicate the flow of wind over the surface.
528679
No, the sun is set to keep shining for a few more billion years i believe.  No it wouldn't go against that law because yeah it might be running down and not getting better but just like you asked in your question it started millions of years ago.  And the universe is much more than jsut the earth.
27787
No, it a is fake calamity brought about by liberal Democrat tree-huggers who despise capitalism. \n\nSure the earth may be warming up but man's activity is not causing it. During the middle ages the earth was a lot warmer and that was before cars were even thought of.\n\nDo a couple of things - check out how long volcanoes have been on the planet, how much green houses gases are spewed into the atmosphere during just one eruption, and compare that to the total output of emissions from man's activity since the internal combustion engine was around.\n\nAlso, look at the facts about the correlation between the energy output of the sun and the global temperature and the correlation between global temperatures and greenhouse gas emmissions from man's activity. You'll find the correlation between the sun's temperature is more closely correlated.
624444
Is there a way to quantify/measure a value for solar radiation with respect to time, it seems to me like you could come up with a calculation based on the angle of the rays. However, I think you would run into some problems with exact calculations due to the nature of our atmosphere (i.e. moisture, dust, etc.)
995661
no.  it changes over millions of years as the universe changes and our relationship to the sun changes, but i'd guess it was pretty close as to what is now.
891052
It requires a bit more than classical physics, but still, you can estimate the sun's lifetime from a very simple calculation. \n\nFirst of all, if you want the current age of the sun (around 5 billion years) this number is determined from radioactive dating of objects in the solar system which are known to have formed around the same time as the sun, as stated in the answer to a previous question. \n\nThe total lifetime of the sun before it becomes a red giant is, as you say, around 10 billion years (meaning that the transition will occur around 5 billion years from now). This can be estimated by assuming that the sun will "die" when it runs out of energy to keep it shining. The time for this to occur is roughly the total energy the sun has that can be turned into light, divided by the rate at which the sun is giving off energy, or: \n\nlifetime = (energy) / (rate [energy/time] at which sun emits energy) \n\nThe rate at which the sun emits energy (its luminosity) is around 3.8 x 1026 Watts (that's the number 38 followed by 25 zeroes - quite a lot of lightbulbs!). This number can be determined from measurements of how bright the sun appears from Earth as well as its distance from us. \n\nThe total energy that the sun has to burn requires a little extra knowledge (for example, some nuclear physics) to understand. We know that the sun shines via nuclear reactions in the core that transform four hyrogen atoms into one helium atom. If you look at a periodic table, you will see that one helium atom has a little less mass than four hydrogen atoms combined; about 0.7% of the original mass has "disappeared". This "missing mass" gets transformed into energy, and this is the energy that causes the sun to shine. Therefore, using Einstein's famous formula E=mc2 for the conversion between mass and energy we have that the available energy in the sun is: \n\nE = 0.007 x M c2 \n\nwhere c is the speed of light and M is the amount of mass in the sun that is capable of undergoing the above nuclear reactions. \n\nNow, it turns out that only the central part of the sun is at a high enough temperature to actually undergo these reactions. You would need to use a detailed model of the sun's structure to figure out exactly how much of the sun is at a high enough temperature, but if we're just estimating things we can say that on the order of 10% of the sun's mass is in the central part of the sun where it is hot enough to undergo nuclear reactions. We then have: \n\nE = 0.007 x 0.1 x Msun c2 \n\nwhere Msun is the total mass of the sun, 2 x 1030 kilograms. We therefore can calculate that the total energy the sun has to burn is around 1.3 x 1044 Joules. Dividing 3.8 x 1026 Watts (the rate at which the sun is giving off energy) into this number gives an approximate value of 10 billion years for the sun's lifetime.