El Niño.

[Curiosity]

Good night everyone, I created this account to ask one question:
how El Niño influences the pluviosity in the south and north of Brazil? I understand that it rains more in the south and is drier in the north, but I do not understand the way it occurs, the mechanisms involved in these situations.
And I did not find any page that explained that. I'm sorry if this is not the right place to ask, but it is the last location I have in mind. I'm also sorry if I wrote anything wrong, English is not my mother language. Thank you, if you need more details please ask.

I thank you all too, for this forum proved to be a font of knowledge that guided me in my journey of making a map.

If I haven't been clear please let me know.

[markem]

My best guess is that El Nino causes moisture to be picked up from the ocean as it passes over it. When El Nino hits landfall it slows down and when it hits the mountains it gets blocked. Both of these things cause the moisture that was picked up to fall as rain. In the United States (especially California) El Nino actually acts to ramp up other weather problems such as the extremely hot and dry winds that cause fires. I'm not sure why and I might be mixing and matching things here but California does have torrential rains in one part and can have the hot winds and fires in another part. I'm betting that if they cut California in half that the rains would be in the upper half and the hot winds in the southern portions. But, like Texas, it is unlikely they will ever cut California in half (or even thirds!). ;-)

[Curiosity]

Yes this is true, but why do it rains more in south Brazil if the Andes blocks the moisture? (and it makes the north Brazil drier too) This is what I don't get.
Sorry for the late response, I almost forgot about it.
Do the wind pass through the mountains after a time? Like, the moisture get blocked, but the wind not? If so, then I think I am a completely noob.

[Azélor]

From what i understand, the Atlantic ocean becomes colder near the northern coast of Brazil during El Nino.? And the temperature increase in southern Atlantic?

if so, cold water bring a high pressure system. This could mean less precipitations.

On the pother side, Peru is affected by a hotter south Pacific current with more rain than usual.

[Azélor]

Southern California is not dry because of El Niño but it amplifies the droughts. It is dry because it is affected by the subtropical ridge during summer only, just like Portugal.

[markem]

Ok. I did some searching online and I found this explanation. Hopefully it helps.