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Topic: Atmospheric pressure and fishing  (Read 25419 times)

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Online Kent

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Re: Atmospheric pressure and fishing
« Reply #40 on: April 24, 2014, 04:33:11 pm »
Oh...and a steady baro ...say over a 72 hour period ...is almost always not good fishing , well maybe NICE weather , but not good catching...BUT...fish still eat....
Just GO FISH!!!


Offline ardinn

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Re: Atmospheric pressure and fishing
« Reply #41 on: August 18, 2018, 07:21:10 pm »
Put together a guide on this recently - Hope it helps explain in a bit more detail!


https://slaneyfishing.com/barometric-pressure-fishy-myth-untapped-resource/

Offline REEFMAN

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Re: Atmospheric pressure and fishing
« Reply #42 on: August 19, 2018, 10:15:59 am »
Great post. Thanks for sharing!

Now is not a good time to go fishing... said nobody... EVER!!

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Offline colin

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Re: Atmospheric pressure and fishing
« Reply #43 on: August 19, 2018, 01:48:42 pm »
 :tkx:  enjoyed the read  :toppie:
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Offline adam

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Re: Atmospheric pressure and fishing
« Reply #44 on: August 19, 2018, 04:07:10 pm »
Very interesting read! Thanks.
"I once caught a fish thiiiiiiiiss big, now pass another beer"

Online CRANKMAN

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Re: Atmospheric pressure and fishing
« Reply #45 on: August 24, 2018, 11:02:53 am »
I agree that atmospheric pressure seems to affect fishing - but I doubt it is as simple as the quoted article states.

My main reason for doubt is based on the weight of water versus air.

The weight of all the air above the water (at sea level) is 1 atmosphere or to make it a bit easier to understand about 1015 mb (milibars).
A big fluctuation in pressure (enough to impact fishing) is around 5 mb.


Above the water this is a fairly substantial change.
Below the water this change can be achieved by varying your depth by only 5 cm!

If fish vary their depth to compensate for atmospheric pressure changes, they would seldom have to change their depth by more than 3 or 4 cm to stay equalized.

If a fish dives 10 metres it will experience double the pressure that it would have at the surface, so I doubt the daily fluctuations of 3 - 5 mb (less than 0.005% of this) would impact it's comfort.
« Last Edit: August 24, 2018, 11:24:54 am by CRANKMAN »
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Offline colin

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Re: Atmospheric pressure and fishing
« Reply #46 on: August 24, 2018, 02:25:21 pm »
I cannot fault Crankman's reasoning or arithmetic  :bow: . Perhaps one of our members can shed light on the matter . :toppie:
My wife allows me to keep all the fishing tackle I can hide.

Offline hookedon

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Re: Atmospheric pressure and fishing
« Reply #47 on: August 24, 2018, 04:18:25 pm »
Just asking , is atmosheric pressure at sealevel 1013 or 1015


Enjoy all discussions involving weather and conditions and WHY they happen

Offline hookedon

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Re: Atmospheric pressure and fishing
« Reply #48 on: August 24, 2018, 05:01:08 pm »
And can someone please explain something to me


Although i dont understand much , i try to go to synoptic charts once a day just to try and get the " bigger picture " of our weather, but what does that thickish line on top or in front  of a low pressure system- with the teeth sticking out, means.


Do that imply the severity of the cold front ,  or what?


Also, in some LPS, the " rings" around the LPS, seems closer than in other systems, what does that imply.


I did try Prof Google, but you know if you dont know what youre asking, he wont help :hehe:

Offline Visenvryheid

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Re: Atmospheric pressure and fishing
« Reply #49 on: August 24, 2018, 07:36:35 pm »
"cold front"
"warm front"
"Isobars"

those are the terms you want to search with..

The line with teeth is a "cold front" denoting cold air (denser and heavier) meeting warm air, the cold air acts like a wedge forcing the warm air up and over it, the colder air is the less water it can hold (less vibration of molecules of gas and less space for water molecules basically) and temperature is a measure of energy. Lift air requires energy and the air looses this at the rate of 1 degree for every 100m, so as the warm and moist air is forced up and over we get clouds, wind and rain..cold front..ahead of that is a warm front sometimes which is the line with the semi-circles which is warm air moving into and getting forced over cold air. The lines of air pressure are "isobars", contours of same airpressure. Air will flow from high pressure to low pressure like water will flow downhill, imagine close lines on a map making a steep gradient, a river will flow very fast down a steep hill, spread out contours the river will flow slow and lazy, same with the wind and isobars. Steep air pressure gradient and air will rush in a clockwise direction (in S hemisphere) from a high pressure perpendicular to the close lines to the low pressure..of course taking into account sometimes there is land in the way and sometimes masses of cold dense air and that makes weather happen either way..sometimes land can squeeze the air out like a sponge as it forces it upwards against gravity and on the other side of the land will be dry..all matric geography, I suggest downloading some coursework and brushing up..always useful.

Anyone see the photo from space of lesotho that was published recently of the snowfall? Shows the effect of having some high mountains in the way of cold wet air quite well..

https://visibleearth.nasa.gov/view.php?id=92617 Nothing biting then but trout ;)

Offline hookedon

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Re: Atmospheric pressure and fishing
« Reply #50 on: August 25, 2018, 07:07:30 pm »
Thanks VeV


I will  do as you say.


hopefully next time it will be more "intelligent " questions.


Lack of matric geography though just make me more dumb, and enquisitive, i suppose.

Offline Visenvryheid

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Re: Atmospheric pressure and fishing
« Reply #51 on: August 26, 2018, 01:12:39 am »
There are no stupid questions, just stupid answers haha

Barometer is relative though..2day the front came over, barometer crashed, then settled at a low pressure when we had our lines out..I got to the parking and someone was packing up and said the wind would blow me back to my car soon enough, bite was slow, wind was MAL, waves were wild, was threatening to rain the whole time didn't look like good fishing weather but then again I got a gallie round 4kg (released) and other guys got a 10kg cracker, both at our feet..so its relative, with no line in the water jy vang niks. :)
« Last Edit: August 26, 2018, 12:28:59 pm by Visenvryheid »

Online Kent

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Re: Atmospheric pressure and fishing
« Reply #52 on: February 25, 2019, 10:21:55 am »
Bearing in mind that NOT all bony fish like a low pressure OR a high pressure and then some bony fish are not as active on either pressure falling OR rising ...BUT a dead steady glass is just plain terrible....
Only way to REALLY use the barometer for effective fishing is to take notes for your specific area and also of note thst barometric pressure can differ as little as 10km along a coast line...making notes and after awhile you will see a trend and its this trend that one needs to adhere to ...


The TREND id your FRIEND!!! :fshn: :fshn:
Just GO FISH!!!


Online Kent

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Re: Atmospheric pressure and fishing
« Reply #53 on: February 25, 2019, 10:37:31 am »
A fish senses pressure changes through its air bladder.
Fish that have small air bladders don't seem to be as affected by barometric changes as those with large bladders. But remember, forage fish they feed on have air bladders, and that alone could have a big impact on where you might find fish and how they behave.

[/size]Fish with large bladders quickly sense when the air pressure is dropping, because there's less pressure on their bladder.
And when there's less pressure squeezing their bladders, the bladders expand a bit.
When their bladders expand, fish become uncomfortable.
They relieve their discomfort by moving deeper or by absorbing extra gas in their bladders. :hnthnt:
Just GO FISH!!!