Let's just say that, if we're talking likelihood, climate change is the "we've already smashed the button and are now debating whether we should get in the vault" category.
That largely depends on to what degree food production collapses in newly-tropical regions. A whole bunch of staple agricultural production isn't going to survive widespread drought and heatwaves, and everyone dependent on those food sources is going to end up very hungry, and taking a hard look at cooler neighbouring regions...
India and Pakistan are both reliant on the Indus River for their agriculture. The Indus has its source in glaciers in the Himalayas. As those glaciers disappear, the Indus will deliver less water, and deliver it much less reliably (melting ice and snow provides a nice steady flow, runoff less so).
So: you have two nuclear powers who are both relying on the same diminishing resource to feed their people. Do you not see how that could cause....tension?
Yes, but that would be a regional, not global conflict. There are already tensions over it and plenty of other tensions between India and Pakistan. the comment I replied to claimed it would cause a "huge global conflict" - i.e. world war. Serious as a war between India and Pakistan would be I would not characterise it in the same way as, say, an all out war between the US and China.
You appear to be forgetting that both India and Pakistan possess nuclear weapons. A war between two nuclear powers has never happened before and the results would likely be calamitous, unleashing a huge global catastrophe and unquantifiable additional conflict as food, health and energy systems fail.
I am not just some random internet person making this up. A lot has been written about this subject by respected researchers: