Microorganism provides the majority of rain condensation nucleation.

[jerrywickey]

Dec 2007 study shows that the vast majority of rain and snow precipitated out of vapor condensing around a micro organism, instead of organic or inorganic inanimate condensation seed. This organism has a density which allows it to float in air indefinitely and contains a gene coding for a protein that is a superior water vapor condensation nucleate.

 

I read it and can not find it now. Does anyone know the study or have link?

 

Jerry

[ecoli]

I've never heard that. Are you sure?

[Mr Skeptic]

New Scientist mentioned this. Apparently the protein helps form ice crystals, which grow enough to fall, either as rain or snow. The bacteria benefits from this because while it can survive in the atmosphere, there really isn't anything to do there so it needs to get a ride down.

[JohnB]

The bacteria benefits from this because while it can survive in the atmosphere, there really isn't anything to do there so it needs to get a ride down.

So how do the bacteria get up ther in the first place?

[Psycho]

So how do the bacteria get up ther in the first place?

 

There are various theories that they could come in from space, such as panspermia, or from volcano eruptions.

 

To get the height of the clouds isn't very hard at all Saharan sand can travel thousands of miles in the air and that is full of bacteria.

[jerrywickey]

It is most likely that the organisms are not extratarrestial. Although I do not discount panspermia, I suspect interplanetary DNA would be greatly limited.

 

There really is no good evolutionary explaination for organisms which are specialized for mid air life. But none the less, stranger has happened.

 

Jerry

[CaptainPanic]

I can believe there are organisms that hitch a ride on a self-made droplet. But I doubt that the majority of droplets is formed this way.

 

Observations from my own window and in my own backyard say that dust particles (aerosols) definitely are good at creating lots of droplets. The best example is New Year. The Dutch are big fans of fireworks, and if there's no wind, this creates a massive amount of mist. It's definitely not just the smoke from the fireworks... it's genuine mist that appeared several times (at least 2005, 2008) only a few minutes after everybody started to light fireworks (so: 1 January, 00:30 hrs - 04:00 hrs).

 

Of course we all know that there are plenty of airborne microorganisms... those should act as aerosols too. But I think there's a lot of dust in the sky as well (airplanes, industry, forest fires, volcanoes). My guess (just a guess) is that the dust outnumbers the microorganisms.

[PhDP]

I also really want to see this study...

[jerrywickey]

http://www.sciencemag.org/cgi/content/abstract/319/5867/1214?HITS=10&sortspec=date&hits=10&maxtoshow=&FIRSTINDEX=0&resourcetype=HWCIT&fulltext=rain+bacteria&searchid=1&RESULTFORMAT=

 

"[ world wide ]... 69 to 100% [of precipitation nucleates] were biological, ..."

 

While dust and fireworks displays do nucleate parcipitation, the long held belief that biology has little to do with rain is apparently incorrect. It seems that perhaps far more than half of rain world wide is a direct consequence of bacteria "deciding" to express a gene coding for a protein which is perfectly suited for nucleation.

 

Jerry

 

 

Other sources

 

http://appl003.lsu.edu/unv002.nsf/9faf000d8eb58d4986256abe00720a51/d807d7193ca91738862573fe004e8ff8?OpenDocument

 

http://www.wired.com/science/planetearth/news/2008/02/bacteria_clouds

 

http://www.eurekalert.org/pub_releases/2008-02/msu-abm022808.php

 

This is an extraordinary opportunity!

 

 

A protein well suited as a precipitation nucleate arising by evolutionary processes allows a great insight into the workings of evolution.

 

This is a great opportunity. One which we do not often have. I would love to begin a concentrated, collaborative, informal discussion of this.

 

Here are some things we know with certainty.

 

1) The organism expressing this protein must have "tested" millions of permutations of this protein to find one this well suited.

 

How many permutations exist? Is the coding identical or are there variations in each species?

 

2) The evolutionary pressure which selects the protein effectiveness exists in the cycle of organisms falling to earth with rain, thereby benefiting ground plants. There must then be some mechanism where organisms which later become airborne benefit indirectly by the ground plants advantage.

 

How responsive could this process be?

 

3) The evolutionary selection of the protein must have been responsive enough to provide for the observed variations or lack of variation in this protein.

 

This is very interesting stuff.

 

Any takers? Anyone interested in investigating this?

 

Jerry

[CaptainPanic]

Thanks for the links.

 

The longer I think about it, the more sense it makes... life is everywhere, so why not also in the upper parts of the atmosphere?

 

How much sunlight would all the microbes/bacteria absorb while they float around up there? (And how much IR radiation from the surface?)

[jerrywickey]

Surely enough sunlight to carry on any photo bio activity the organism needs but considering the surface area of each organism and the number of organisms the surface area ratio to area of sunlight is insignifcant. No effect.

 

However, the biological effects may be tremendious. Much more study is needed. But it could turn that the planets ecosystem is much much more responsive and adaptable than we ever imgined. The ground plants and animals, including humans, may be able to turn on or turn off rain at will. Sub conscience chemical signals may be telling these organisms when to turn rain on or off.

 

If that is so, it is likely other planetary systems, we thought was abiotic might turn out to be under biological control as well. If that is the case, we have nothing ecologically to worry about on this planet. The planets responce will be appropriate and very adequate. However, if the planet can bring to bear as powerful of a responce as rain making organisms suggest, we will not be able to significantly alter the planets responce to any environmental changes.

 

This does not mean that we will like the responce the earth choses to any environmental issue. In fact it may well be to our great disadvantage. It only means that if the earth can bring to bear that much power, we likily have little chance to change it.

 

Jerry

[CaptainPanic]

There's something that is / was confusing me...

 

We have a lot of dust in the air (man made with known origins, such as smog and other dust clouds). We know that this blocks a significant amount of sunlight... the best tests were done in the days after 9-11 when the daytime temperature was 1 degree hotter, and the night about 1 degree colder. (http://www.stanfordreview.org/Archive/Volume_XXXVI/Issue_8/Opinions/opinions1.shtml - read the 8th paragraph)

 

Fine dust (which is man made) is classified in several categories: PM1, PM2.5, PM10... where PM stands for Particulate matter, and the number is the max. size in micrometers. PM10 is the biggest as far as I know. PM0.1 is the smallest. This is generally referred to as UFP (ultra fine particles). http://en.wikipedia.org/wiki/PM10

 

Bacteria are all prokaryotes, and according to wikipedia, that means their size is about 0.1 - 10 micrometer... The same as man made dust. http://en.wikipedia.org/wiki/Bacteria

 

There are now two possibilities.

 

1. The airborne bacteria are smaller, and wikipedia's page on bacteria does not include these airborne bacteria. In that case they may block less sunlight, but can still provide more nuclei for water to condensate.

 

2. The airborne bacteria are the same size as other bacteria we know. In that case I still cannot see why they have no effect on blocking the sunlight, even without any condensation of water. Dust can definitely block sunlight without any condensation of water (smog in big cities, and the dust cloud that occasionally crosses the pacific from China to California are some examples http://science.nasa.gov/headlines/y2001/ast17may_1.htm). If it is true that there are more bacteria in the sky than dust particles, then they should have a significant effect on the planet's energy balance (blocking the sunlight and IR radiation, as well as cloud formation).

 

3. (When there's two possibilities, there is always a third) - Maybe these bacteria find a way to stay closer to the ground? Most rain clouds are not stratosphere giants, but stay within the first kilometer of the atmosphere. We should get a handful of these bacteria, and fluidize them in a bed, while checking their structure with some spectroscopy. I would like to know if their structure changes with changing pressure. Perhaps they are more sophisticated pilots than a (dead) dust particle, and perhaps they have an altimeter.

[jerrywickey]

1. Air buoyancy is not dependent on size. Reference a blimp. The organisms may be much larger but less dense due to their structure as directed by their genetics. They may also be transparent. Reference the proteins which make the lens of our eyes.

 

2. They may also be transparent. Reference the proteins which make the lens of our eyes.

 

3. They seem to be present at the altitude that 69% to 100% of rain nucleates.

 

Jerry

[CaptainPanic]

1. Air buoyancy is not dependent on size. Reference a blimp. The organisms may be much larger but less dense due to their structure as directed by their genetics. They may also be transparent. Reference the proteins which make the lens of our eyes.

 

2. They may also be transparent. Reference the proteins which make the lens of our eyes.

 

3. They seem to be present at the altitude that 69% to 100% of rain nucleates.

 

Jerry

 

The link you provided earlier (http://www.wired.com/science/planetearth/news/2008/02/bacteria_clouds) suggests that the bacteria are of the family of P. Syringae (http://en.wikipedia.org/wiki/Pseudomonas_syringae). Wikipedia states nothing about transparency or buoyancy of these bacteria. The bacteria have a flagella (sort of a tail), which increases their drag in a fluid (air) and this might enable them to fly. This means that their density is higher than air, but the air resistance they find is so high that they can still fly. This is a size-dependent phenomenon. I therefore disagree with your first argument, and I still challenge the claim that microbes play a larger role than dust in nucleation of rain.

 

And I also doubt that the bacteria are transparent. Even the lens in our eye is not fully transparent. It does not let IR radiation through. It also absorbs some UV radiation... it happens to be UV that comes from the sun (not absorbed in the atmosphere).

 

Frankly, I don't believe in transparent bacteria that are lighter than air, like a blimp. They would be flying micro-bombs in stealth mode, full of hydrogen or methane (how else would they fly? Bacterial helium separation from the atmosphere is just nonsense).

[jerrywickey]

You simply didn't read the whole post.

 

I was responding to a reply which suggested it was all impossible. I was simply suggesting from the top of my head possible ways a microorganisms might accomplish what was observed.

 

You are correct, air resistance against a long flagellum would keep it airborne. And considering size of the organism to the area of sunlight, transparency is not needed.

 

Your challenge to the claim that microbes play a larger role than dust is in direct opposition to the findings of the study, which found 69% to 100% of the various samples they examined were nucleated by this protein.

 

Jerry

 

It seems more diffucult for some than for others to adapt to new discoveries.

[CaptainPanic]

Could you please clarify what I did not read? I have tried to read everything provided in this thread before answering. If I caused some miscommunication then I apologize... but I am not aware of it.

 

I did read that researchers found that 69-100% of the nuclei in some samples collected by the researchers were of bacterial origin.

 

I still claim that dust is a major factor in the energy balance of the earth. There's lots of it... (I provided several links in post #13). Yet if bacteria cause 69-100% of the nucleation, then I ask: Where are they? They were only found in a number of samples... So far I have provided several world-scale phenomena that are dust-caused. Yet all the proof that nucleation of precipitation is caused by bacteria is small-scale (samples taken at several locations on the surface of the earth).

 

p.s. I realize that my questions are not answered in the articles so far provided in the thread. I actually did read most, if not all. I hope you can understand that I keep defending my claims in order to get more information. Asking the right questions is very important.

[jerrywickey]

I apologize. Looks like you read what I thought you didn't. It is just that you don't accept some of the findings. Fair enough.

 

Jerry

[CaptainPanic]

No worries

 

Guess we both just have to wait for more data to finish this discussion (or join the research, and hunt for it ourselves, something which I won't do, sorry...).

[jerrywickey]

Yup

 

I think you are correct. The only thing we could do is explore the implications of each of the possibilities I identified. What a waist of effort, since only one of them will be correct.

 

Jerry