Broadly, I see three possible domains of activity:

- For technological development

* anything that explores additional renewable Energy sources (like the Pelamis Wave Energy converter). AS it is a tricky and multi-fac3eted problem, there is infinite room for improvement and better technologies.
They will probably not be economical quickly but they do have the potential to average-out wind and solar fluctuations cheaper than with battery technology, because ocean waves for example can be harvested later and far away from their origin. here an example:

https://en.wikipedia.org/wiki/Pelamis_Wave_Energy_Converter

https://www.youtube.com/watch?v=l3-SXFtPYe0

* a lot of things which are related to energy management. For example, there exist already commercial energy weather forecasts which predict the generation by wind and solar energy for about the next 48 hours, and help to make balancing energy cheaper because the quickest sources are the most expensive

* anything which makes energy consumption, especially heat and cooling, more adaptable to renewable production. For example, cold houses can be cooled at times of the day where is a lot of wind energy, and can use up that reservoir when there is less cheap electricity available. This principle can also be used in the household, e.g. in washing machines which wait for an excess of solar energy.

- the second domain I think is the political realm - climate change is a political problem and it will take a lot of political pressure to do something about it. There can be interesting sub-task for technical people. For example, online carbon footprint calculators can help people to make better decisions and estimate quantitatively what impact their life-style has (and this can, in turn, also inform political processes. A good one, but specific for Germany, is this one: https://uba.co2-rechner.de/en_GB/

- The third realm I think of is to fight misinformation on climate change and climate-saving policies. There are organized campaigns which work nearly like information warfare, against the interests of all of humanity. There are some organizations which work to uncover anti-climate lobbying, like desmog.org:

https://www.desmog.co.uk/55-tufton-street

Similar and often interreolated to pro-brexit think tanks and lobbying groups, it is not a far stretch to guess that they will use similar tactics. Now, for Brexit, a few citizen-invastigators have done a lot of work do uncover misinformation campaigns. A few examples:

https://www.theguardian.com/technology/2017/may/07/the-great...

https://bylinetimes.com/author/jamespatrick/

https://bylinetimes.com/sections/fact/page/20/

https://bylinetimes.com/2019/11/05/the-box-set-byline-times-...

https://www.theguardian.com/uk/2012/dec/05/police-whistleblo...

https://twitter.com/search?q=%40agoodfireburns%20misinformat...

I think what is needed is more citizen journalists / investigators which expose how misinformation about climate change is formed and spread. This can be helped by forensical techniques that, for example, detect bots in social networks and how they are coordinated. It is probably a kind of sharks basin which won't be comfortable for most people, but it is very needed that this gets exposed more.