Young researcher hoping to volunteer for Antarctica fieldwork
Try the long game:


Start reading up on the research that is being done.  For the interesting ones, start corresponding with the authors asking questions about the work.  They have to be good questions, showing that you know what you are talking about.
Look at who funds each researcher.  Check the papers for those 'thank-yous' that give credit to various individuals and institutions.  Check the institutions to see how they hire support personnel.  If you can't get a job as a researcher, look at getting a job just as a tech.
Most researchers are connected with one more more institutions.  Some of these specialize in polar science.  Some may supply support crews that span scientific disciplines.  E.g. They may have a pool of snow-cat operators that any of the scientists can draw upon to move equipment and personnel.  This is more likely with the permanent bases.
Can you speak well?  Do you have a large grasp of polar science in many fields?  Look at being a guide on the cruise boats that go to the arctic.  If you are quick witted, and can reduce difficult topics to digestible chunks, this is a possibility.  Train for it by writing a science blog.
Write a polar science blog.  Turn dry science into good clear interesting commentary about what's happing, how it happens, why it's important.  This becomes something to put on your resume, and if you get a decent following may itself get you there as a science journalist.
Prepare yourself. Learn how to dress and take care of yourself in Arctic regions.  Someone they don't have to train as much is cheaper for them.
Consider having your appendix removed.  At one point this was recommended as an appendectomy in Antarctica is double plus un-fun.