Comment by defrost | Hacker News Reader

Comment by defrost | Hacker News Reader

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(1) yes, will have an additive warming effect

(2) no, unlikely to be having any effect yet

(3) maybe noticably at ground level for five years .. perhaps measurably (with sensitive instruments looking at the right things) at the tropopause and above for a bit longer.

In context "∼10% of the stratospheric burden" means that all in one hit the stratosphere got about 10% of the maximum water load it can carry (before physics makes any extra fall away).

As I understand it the stratosphere was running a bit under "normal" water load, so this rates as a top up and a bit of a push over 'normal' - the main thing that longer term models will look at is how this plays out the longer term rise and fall of water being pushed up into and sucked back out of the stratosphere through tropical storms and other such actions.

The (2) "no, not yet" is due to more lag than you might expect - it only happened 18 months ago and we are still lagging on the expected heating due to occur due to increased thermal insulation from CO2 released into the troposhere five years ago.

The key phrase from both the JPL presser release and source paper is:

    The effect would dissipate when the extra water vapor cycles out of the stratosphere and would not be enough to noticeably exacerbate climate change effects.

It's on a 'short' (decadal) time scale and atmosphere wonks will absolutely notice the effect, for many others it'll be just another transient minor factor in a bigger picture.

Or not .. but that won't surface for another few years yet in anothr research paper.

I'm a bit doubtful that it (assuming there is an "it") takes more than 1.5 years? 18 months is 30% of five years. A process that takes X amount of time can't really take Y >> X amount of time to get going.

>we are still lagging on the expected heating due to occur due to increased thermal insulation from CO2 released into the troposhere five years ago

I thought it's being widely reported - this year - that we seem ahead of the warming trend, breaking all sorts of records, etc.

As is mentioned in almost every article about climate change ad nauseum, global temperature increases measured in degrees are small but involve huge amounts of energy, and typically there is said to be a linkage to massive disruptions and suffering.

So saying this temporary source of warming is very small and unnoticeable seems rather equivocal. You can say it, but what is it meant to communicate?

Small and unnoticeable on your thermometer is literally true of the primary trend from CO2, but if you go around belaboring that, you sound like a denier.

> A process that takes X amount of time can't really take Y >> X amount of time to get going.

A fully laden iron ore carrier 1 km in length with 100's of thousands of tonnes of mass can drift slowly toward your ore wharf and take an hour to first touch it.

The destruction of that jetty can be over in 20 minutes.

There's a lag time of 60 minutes on an event that lasts 20 minutes.

> I thought it's being widely reported - this year - that we seem ahead of the warming trend, breaking all sorts of records, etc.

Right now the global average tempreture is higher than it's been in recorded history.

This is caused by greater insulation in the atmosphere trapping heat that is normally reflected outwards in the thermal band - that insulation is greater CO2.

Here's the thing; were we to magically stop ALL CO2 emissions right now today and hold steady .. the global average tempreture would still continue to rise for many many years (smoothed over thhe usual decadal oscillations) until an equilibrium was reached .. that's the lag time.

You may be familiar with a similar lag on a cold night when you throw an extra blanket or six on the bed and you're not instantly warm .. it takes some time for your body heat to warm up the area under the blanket.

A good starting palce for all this is the heat equations - heat flows like a fluid, it takes time to travel through mediums such as metal bars, it takes to to radiate heat away, etc.

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