## 4 Conclusions and Future Work
This work, while purely technical, is in our opinion a groundbreaking step towards bringing open-source, inexpensive, easy to build, modular, power-efficient instrumentation to the field of in situ study of waves in ice in particular and oceanographic measurements in general. Indeed, our design has also proven to be highly efficient both as a traditional open ocean drifter and wave buoy. We expect that this design will significantly reduce the barrier to entry for new research groups to monitor waves in ice; sea ice drift patterns; and similarly, wave activity and ocean upper layer drift and currents in the open ocean; and be a possible platform for public outreach since the design is simple enough to be assembled for example by high school students. This design can also be used as a basic building block for setting up a variety of instruments--such as weather stations, environmental loggers, and wildlife monitoring instruments--by connecting specific sensors and adding extra modules to the firmware, while taking advantage of the power efficiency and iridium connectivity of the main electronics board. Another key improvement brought by the present design is its very limited weight and size. Typically, our implementations of the design occupy a space of 12 cm \(\times\) 12 cm \(\times\) 9 cm and weight between 0.3 and 0.5 kg. This is small and light enough to be deployed, for example, from a medium size quadcopter drone or from a fishing rod several meters long. This could prove very important in practice when releasing large numbers of drifters in the Arctic and Antarctic, since (i) changing the course of an icebreaker and forcing it to make many (even short) stops to put instrumentation on the ice has a large footprint on the operation of the ship and a high cost, while (ii) flying a quadcopter drone to deploy instrumentation on the ice, or dropping instrumentation on-the-go while the boat is steaming using a long rod, would have zero marginal cost for an expedition. As a final technical word, we want to say that, while we have released the instrument design, code, and validation data already since we believe that it may already be of value for other groups, there are a number of ongoing improvements that are taking place and will continue after this paper is published. First, we are working on adding the possibility to store large amounts of data using a two-step memory setup (i.e., a Ferromagnetic RAM for fast, low-power storage of data on the fly and a SD card for slow long-term archiving). This will make the instrument even more valuable in contexts where it can be recovered after deployment, since this will allow us to store and recover time series that are, at present, only stored temporarily in RAM for performing wave spectrum computation. Second, we will work in the future on adding full-directional wave spectrum information. Finally, when these additions are done, a major code rewrite, taking into account all the lessonslearned while developing this instrument, will be performed to make the code even easier to extend, test, and reuse. When these further refinements are implemented, we will also consider designing an open-source printed circuit board, to lower even further the amount of work needed to assemble the electronics of the instrument. Ultimately, if there is interest from the community, we hope to provide an all-in-one, fully integrated, low-cost electronics boards that will be a true turn-key solution. Conceptualization, J.R., T.N., M.M., O.B., J.V., L.R.H., T.W., M.J. ([PERSON]), G.S., M.J. ([PERSON]), K.H.C., A.G., J., O.G., A.M. and A.B. ; methodology, J.R. and T.N. ; software, J.R., G.H. and P.B. ; validation, J.R., T.N., M.M., O.B., J.V., L.R.H., P.B., T.K. ([PERSON]) and T.K. ([PERSON]); formal analysis, J.R., T.N. and P.B. ; investigation, J.R., T.N., M.M. and [PERSON]; resources, [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] ([PERSON]), [PERSON] and A.B. ; data curation, [PERSON], T.N. and P.B. ; writing J.R.; visualization, [PERSON], T.N. and P.B.