If you needed to (as in a Disaster Recovery scenario), you'd just flip on "On-Demand I/O":
https://cloud.google.com/storage/docs/on-demand-io . There will be a surcharge of $0.005 per GB of data transferred that goes over the 4 MB/s of throughput (
https://cloud.google.com/storage/pricing#on-demand-pricing).
Disclosure: I work on Google Cloud (but not Nearline).