> So to prepare for drier weather that's likely to come with climate change.
I don't understand why do so many people equate climate change and global warming with drought?
If only it was only that simple?
One of the most noticeable, measurable effects of climate change is the warming of the oceans.
That warming adds energy to the oceans and that energy then causes big changes to barometric pressure, resulting in wind directional changes.
The warming oceans warm the air above them and that causing the air to rise. That rising warm air sucks in colder surrounding air. That air movement changes the prevailing wind patterns.
It is those changes to local wind patterns that cause the changes to local weather. If suddenly you’re country is seeing more onshore winds, you’ll be seeing more drought. But if you’re seeing more offshore winds you’ll see more flooding.
The climate models are so complex it’s impossible to predict how these changes will pan out at a local level.
But as someone living here in Oz, it's clear that over the last few years the local wind patterns have changed and those changes have caused changes to local weather.
Some areas are seeing warming, others are seeing cooling, some areas are in drought, others are in constant flooding, but in the end it just depends on how the the prevailing winds have changed.
The models may well have changed, but a quick Google for "climate change impact Costa Rica" brought up a 2008 study, saying:
> Regional climate models predict that the area will become warmer and drier as climate change accelerates.
Give them the benefit of the doubt. Perhaps they are talking specifically about the best current models for Costa Rica, instead of suggesting every place will have drought.
Although the models are complex and may change, there's no reason not to run with the best current models, changing your plans only when these long-term forecasts change.
Here's a 2013 study in Nature on the subject[1]. Drought has increased over many land areas since 1950, pretty well matching their model, which predicts increasingly severe drought over the next 30-90 years.
For much more on the subject, a great book is Six Degrees by Mark Lynas, who reviewed about 3000 papers on the projected effects of climate change (and referenced them extensively). I don't remember all the details, but one issue is that more heat brings more evaporation, drying out the soil. Rainfall tends to be less frequent and harder, which washes away the dried-out topsoil.
Another issue is that rain clouds tend to form over the warmer ocean, instead of drifting over land. Rain falling in the Indian Ocean is expected to cause severe drought in Africa (and that's already been seen to some extent).
I don't understand why do so many people equate climate change and global warming with drought?
If only it was only that simple?
One of the most noticeable, measurable effects of climate change is the warming of the oceans.
That warming adds energy to the oceans and that energy then causes big changes to barometric pressure, resulting in wind directional changes.
The warming oceans warm the air above them and that causing the air to rise. That rising warm air sucks in colder surrounding air. That air movement changes the prevailing wind patterns.
It is those changes to local wind patterns that cause the changes to local weather. If suddenly you’re country is seeing more onshore winds, you’ll be seeing more drought. But if you’re seeing more offshore winds you’ll see more flooding.
The climate models are so complex it’s impossible to predict how these changes will pan out at a local level.
But as someone living here in Oz, it's clear that over the last few years the local wind patterns have changed and those changes have caused changes to local weather.
Some areas are seeing warming, others are seeing cooling, some areas are in drought, others are in constant flooding, but in the end it just depends on how the the prevailing winds have changed.