Is man responsible for the jet stream?

The jet stream is positioned based on solar activity and ocean/atmospheric conditions. It is further north during a La Nina pattern (cooling of the eastern Pacific), allowing favorable conditions for hurricanes to form in the mid-Atlantic. The jet stream is further south and disrupts hurricanes in the mid-Atlantic during an El Nino (warming of the eastern Pacific). This is a blocking event relative to hurricanes in the Atlantic, Caribbean, and Gulf of Mexico.

The oceans warm and cool relative to seasons and more significantly to Earth's distance to the sun. During aphelion months (June, July, August) when we are about 3 percent further away from the sun, ocean temperatures cool. During perihelion (December, January, February) when we are closer, ocean temperatures get warmer. There is a lag, so cooling laps over into September and October, and warming laps over into March and April. Many hurricanes are spawned over central Africa as thunderstorms that twirl off into the eastern Atlantic and intensify with warm tropical waters.

Human influence in any of this? Much the same as that of the fluttering of a butterfly wings. Sure there's an effect, but negligable to the point of insignificant. Yeah, it's simple: small factors have small effects. Is temperature rising? Yes, because it was cold! Where's the climate model that shows warmer temperatures bringing fewer La Nina's and therefore fewer hurricanes?

Global warming certainly would be expected to affect the position of the jet streams. In fact, there is evidence that the jet streams have moved poleward over the last several decades, as would be expected in a warming climate (see link below). Poleward movement of the jet streams would mean that warm air would tend to intrude farther poleward also, which may lead to stronger heat waves in places like Russia. I have not seen any research on the whether or not blocking events in particular would become more frequent, although it would not surprise me, since that would seem to be in line with other model predictions.

As I've said before, though, individual events like the floods in Pakistan or the heat wave in Russian should not be blamed on global warming or used as evidence against it. You would need a much longer study that would encompass many such events before you'd have clear evidence one way or the other.

http://www.agu.org/pubs/crossref/2008/2008GL033614...

EDIT: After posting my answer I read some of the other answers. Some are completely specious mumbo-jumbo, and essentially resort to the religious argument that man is insignificant on the planet and can't possibly affect things such as the jet stream. It would be nice if this were true, but just saying that does not make it so, and there is ample evidence to the contrary.

It is man's fault because we are adding a little more CO2 then we were 150 years ago. If you read any of the climate reports on climate change you will know that climate scientists don't like to break off the exact number that is man's responsibility. Also, according to the AGW crowd, anything that isn't within what they think is "normal" is caused by man's CO2 pollution. They also don't want to acknowledge that these events have occurred sporadically off and on since we exited the last major ice age around 12000 years ago.

Study the doctrine of the depravity of man....you will find out why....we can't want God on our own and apart from the Holy Spirits intervention we would never come to God on our own...we can't...Christ said no one comes to Me unless my Father draws him....the word draw there literally means to drag...Study the nature of man and the depravity of man and you will learn a lot about why people hate God so much That is why all these so called "atheist" hate God so much...you see how hateful and angry they are with all their comments...it is because they are aware of the fact there is a God and they hate Him...they don't have a neutral view of God they actually hate Him they even go to the point of saying they don't believe when they do....they hate Him so much they wish He didnt exist but He does and they know it..

Yes man is responsible for the jet stream. But only white, conservative, men. We are also responsible for the Rocky mountains and the Great Lakes but since these can't be linked to global warming we don't get credit for them.

no because the jet stream isn't evil yet, but if the wackos deem it evil in the future like they did co2 then i'll change my answer to yes

No bro, man not responsible for jet stream, that happen naturally, or so long we all think it happen as part of nature. Man made climate change, or AGW as many here like to call it, neva shown to be real, just imagination of lots of people who think they know something. They like "oh it getting warmer, yeah? Must be man's fault, he bad. One guy wrote here last year that global warming cause very cold weather last winter??? So weather hotter, but cause colder weather too?? This guy serious, yeah?

Peace to you and aloha from Hawaii

The WMO also includes that calving of the largest recorded iceberg off Greenland (in 50 years of measuring) as another extreme weather event this year.

Global warming increases the frequency of extreme weather events largely through increased evaporation. Also, as Dana mentioned, warmer oceans cause the circulation of weather patterns to change.

Increased temperature increases evaporation which increases water in the air and decreases moisture in the ground. This can cause both extreme heat and extreme precipitation.

Following the 2003 summer in Europe, one study concluded that global warming had doubled the likelihood of such an intense heat wave. Even doubled, the odds of such a heat wave were very low -- but still double what they would have been naturally. When natural factors influence the weather, global warming increase the odds of the weather becoming extreme, whether heat or rain. This is projected to happen in the models, had been seen since 1970 but with a lot of natural noise that prevents certainty, and now has been seen in a particularly unusual year in 2010.

The jet stream is like El Nino.

Alarmists know the phenomena exists, but use the results of it for their propaganda, while knowing nothing of the cause or behavior.

The long term forecasts of my friends who are jet pilots have been outstanding.. primarily because they spend a lot of time actually IN the jetstream, and know where it is and how long it's been there.

A solid consensus? Since when do you think consensus matters? I see, as long as scientists tell you what you want to hear, that's when we should listen to them. Got it. Seriously though, while I think a scientific consensus demonstrates scientific credibility, you obviously don't, or you wouldn't dispute that humans are causing global warming. So why are you talking about a supposed consensus on this subject?

I think you're oversimplifying. According to Kevin Trenberth, "Such circulation patterns are normal, but they’re also being enhanced by rising sea temperatures due in part to global warming...For instance, the northern Indian Ocean has warmed 2 degrees Fahrenheit (1.1 degrees Celsius) since the 1970s. Warmer water releases more moisture into the air, which can supercharge monsoon rains."

http://www.dawn.com/wps/wcm/connect/dawn-content-l...

So yes, these weather events were mainly caused by the jet stream blocking event, but it's not accurate to say that global warming didn't contribute to their intensity, which is all we've been saying. Global warming will continue to make extreme weather events like these more frequent. That's simple reality. It doesn't mean that floods and heat waves wouldn't happen if not for global warming. It doesn't mean that every extreme weather event is caused by global warming. It just means that on average, global warming will make this extreme weather more frequent and more intense than it would have otherwise been.

It's pretty simple logic. Hotter temps mean more water vapor in the atmosphere, which mean stronger storms. Hotter temps also mean heat waves are more likely to happen. Do you disagree with this simple logic?