If humans aren't causing global warming, why is the planet warming more at night than during the day?

Question

Diurnal temperature range (DTR) is the difference between the daily maximum (daytime) and minimum (night) temperature.

On average, during the 20th century the DTR decreased. Average night temp warmed more than day temperatures.

http://www.grida.no/climate/ipcc_tar/wg1/fig2-2.htm

"Observed DTR over land shows a large negative trend of ~0.4 C over the last 50 years that is very unlikely to have occurred due to internal variability. This trend is due to larger increases in minimum temperatures (~0.9 C) than maximum temperatures (~0.6 C) over the same period."

http://www.bom.gov.au/bmrc/clfor/cfstaff/jma/2004GL019998.pdf

If the Sun is causing global warming, obviously the planet should be warming more during the daytime when it's hit by solar radiation.

If greenhouse gases are the cause, it effects both day and night. Increased cloudcover can block sunlight during the day and decrease DTR.

How can decreased DTR be explained if not by anthropogenic global warming?

Francis - as stated in the first link, the temperature stations used were all in rural areas. No urban contamination.

Keith C - your question is not relevant to this discussion, but yes, I do.

http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png
http://en.wikipedia.org/wiki/Image:Holocene_Temperature_Variations.png

Francis - I did refute it. You can ignore that I refuted it, but that doesn't change the refutation.

Tomcat - PDO is cyclical, and increased solar radiation would warm the daytime more. Increased water vapor might make the DTR increase less, but it would still increase.

Mikira - how do you propose that cloudcover would only increase at night? What would cause this?

mjmayer188 - We do know. Greenhouse gases are causing global warming.

http://answers.yahoo.com/question/index;_ylt=AkrpFY07cYlN4lwS07hKFgXty6IX;_ylv=3?qid=20071215102828AAxyWW6

bigdmizer - Second link, Table 1. Standard deviation for DTR is 0.04. Figure 2 plots the values of temperatures and DTR with error bars.

Not sure where you're pulling those numbers from. Probably your nether-regions.

qu1ck80 - no, my wife uses the car to commute to work!

I like your idea for a global warming Mythbusters though!

Answer 1

Let me summarize some prior answers. If the earth receives more energy from any cause, there will be more water vapour in the atmosphere. Water vapour has latent heat that can be released on cooling to moderate the cooling. This is a nice and perfectly correct argument, but if one digs a bit deeper there is an underlying assumption that the Earth is isotropic and enough water is available everywhere to act as a buffer. The data shows a decrease in the DTR over deserts (Sahara, central Asia, Patagonia, Western North America, central Australia) as well as humid regions. The problem with the water vapour latent heat hypothesis is that water vapour is in short supply over desert regions. CO2 has increased everywhere, water vapour has not.

The decreased DTR over deserts cannot be explained by increased solar radiation. Solar radiation has not changed significantly, but for the sake of argument suppose that it increased by 1%. During the day the desert would certainly get warmer. By the Stefan Boltzman Law the rate of emission would also increase as T^4 (T in Kelvins). In the absence of a greenhouse gas, the net effect is that the DTR should INCREASE with more solar radiation. The observed trend is in the opposite direction.

Answer 2

"The ice age existed. Everyone agrees on that. The ice age ended. Nobody has asked how it ended... if just one day POOF everything was warm? Or, did a gradual warming cause the ice age to end? Humans could not have caused the end of the ice age." But we know what did, Keith P goes over what happened the way a skeptic would (an actual skeptic, not a claimed skeptic that just denies the fact of global warming). If you didn't understand that the basic reason is that we know when all the natural cycles occur and it just so happens that we aren't in a warming cycle (and there hasn't been any correlation with solar activity for a while either) "What real evidence is there that humans are causing global warming? Freon is heavier than air, so it sinks and never reaches the ozone." Aside from there only be a tangential relation between the hole in the ozone layer and global warming the CFCs do very much reach the stratosphere since the stratosphere is within the heterosphere where the atmospheric gases are well mixed by atmospheric turbulence (and it's enough to get things far heavier than CFCs up to the turbopause). But think what you're saying, CFCs are heavier then air, so is carbon dioxide so you'd expect CO2 to sink and form a layer of CO2 on the surface upon which is the layer of molecular oxygen and then the layer of nitrogen and then the layer of atomic oxygen. That's just not how the atmosphere is below 100 km.

Answer 3

I agree with Tomcat. Increasing greenhouse gases should moderate the temperature and the warming should be more on the coldest part of the night and in winter. This should be true if it is CO2 or water vapor. Does anyone suggest that this is a bad thing. Far more people die of cold than warm. Far more animals will also die from cold, especially those cold nights and cold winters. Why is it that warmth is seen with such scorn by the the GW alarmists that they apparently will be happy with nothing short of cooling. Climates fluctuate. They always do. It is far better overall when they they warm IMO and moderation is even better.

Answer 4

Increased greenhouse gases would explain the nigh time temperatures. My question is do greenhouse gases cause global warming or is global warming increasing the amount of greenhouse gases in the atmosphere.

I've seen arguments that seem to prove both arguments. At this point, I really don't think we know.

Answer 5

Its all in which data set you use and what other studies are taken into consideration. the global warming theorists are ignoring or discarding studies that throw a wrench into their claims and of course the discounters are focusing on doing just that.

There is currently controversy over contamination even in the non urban areas where the monitoring is done.

And there are studies that contradict or throw in unconsidered variables to the things you are stating per the articles you quoted.

point is this is a very agenda driven issue. not agenda driven by the common person. But by the organizations that are seeking to prove or disprove it.

Answer 6

The PDO increased the amount of water vapor in the atmosphere, or the increased solar radiation over the last century allows more H2O to reside in the atmosphere at any given time. Can you say positive feedbacks?

Answer 7

Dana - It all depends on cloud cover. In the winter if we had sunny skies during the day to warm us up. Then get clouds rolling in around sunset that sticks around all night we get a bit warmer during the night, due to the clouds keeping the heat from escaping into the atmosphere.

We are colder in the winter when the skies are clear and cloudless all day and night, because any heat we get during the day gets sucked away at night.

Edit: I wasn't stating our even inferring that cloud cover would only happen at night. I was just explaining how night time temperatures could increase at night, since I've experienced it happening and I'm very observant.

There are a multitude of things that cause cloud cover to either increase or decrease any time of the day or night. The jet-stream can bring them in from anywhere on the West Coast, where high and low pressure systems are located, which can cause hot and cold air to converge, which causes a disturbance in the atmosphere. (I've watched many storms develop over my life time and clouds can seem to just appear out of no where.)

Edit: Another thing that comes into play is where the air is coming from. And again the jet stream plays a big part in where air is drawn from. If the jet stream draws air from the North, which it usually does starting in January we get subzero temps, if it's drawing the air from the South we get milder temps in the winter and hotter temps in the summer. The jet stream seems to never take a straight path across the US, so it's rare to get weather directly from Seattle to Minnesota. A lot of our Weather in the winter either comes from the North or if a major storm happens to the South it seems to like to makes it way up here.

But this question you asked has more to do with weather patterns than climate.

This also proves to me how full of it they are, since when did the rule of heat rising get changed? So if the deserts are retaining more heat than the sun has to be heating the ground more during the day, so that the heat that rises from it at night doesn't dissipate as fast.

Answer 8

Hey Dana!

Nice to see your questions, and concerns.

Has anyone figured out yet that anything that we do to our environment will have some sort of impact? This alone is justification for action. The "ignore greenhouse gases" approach is like not telling a kid to look both ways before crossing the street after he is halfway across!

Someone else in here referred to global warming as a hoax like Y2K. Let me tell you from first hand experience Y2K was not a hoax, and a lot of us worked very, very hard to prevent a lot of malfunctions! I was in charge of 8,000 computers at the time, and only one of mine went down. If the updates had not been done, 2,000 would have crashed.

Anyway, I think global warming is a feasible theory, and to do nothing would be foolish!

Answer 9

Dana,
Did you read the links you posted as your support for your argument?
I find it funny, because if you did then you didn't read it throughly.
Please read them again, because when you do you will find that there is standard deviation of ~0.5 C in the statistics you cite as evidence.
That is essentially a margin of error of ~0.5 C! You cite a warming trend of ~0.4 C!
Your argument is BUNK.

Answer 10

DO you have a graph that shows warming over a longer period? 100 yrs is like looking a dot and knowing what the painting is