Some touches on the new budget notebooks

budget/README.md

@@ -1,7 +1,7 @@
 # To close budget on particles
 
-The way to close tracer budget on Lagrangian particles is relatively easy. Please referred to the functions in eulerian_budget and lagrangian_budget. So far, I have not gotten the time to make an illustrative example, but the api references are ready to go.
+The way to close tracer budget on Lagrangian particles involves quite a bit of [math](https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024MS004848) but I think I have made the software relatively easy to use. You can get started with the [notebook examples](https://macekuailv.github.io/seaduck/bud_tut.html). You can also find the [eulerian_budget](https://macekuailv.github.io/seaduck/api_reference/apiref_eulerian_budget.html) and [lagrangian_budget](https://macekuailv.github.io/seaduck/api_reference/apiref_lagrangian_budget.html).
 
-If you would like to use this functionality but have some difficulties, please email me (Wenrui Jiang) at wjiang33@jhu.edu. I am happy to share my code, explain things, and potentially get more involved on your project.
+If you would like to use this functionality but have some difficulties, please email me (Wenrui Jiang) at wrjiang@mit.edu. I am happy to explain things, and potentially get more involved on your project.
 
-If you want to contribute to the package by helping me make the budget code public, also email me. I don't know how to thank you enough.
+If you have suggestions on how to make the budget code more accessible to the wider audience or improve it in other ways, please also email me. I don't know how to thank you enough.

docs/bud_tut.md

@@ -1,8 +1,6 @@
 # Tutorials for Lagrangian tracer budget
 
-```{tableofcontents}
-
-```
+The following notebooks shows how you can close a tracer budget with Lagrangian particles. They focuses on how this method is implemented in `seaduck`'s `eulerian_budget` and `lagrangian_budget` modules, rather than the rigorous derivation. Interested readers should refer to [our paper "Tracer budgets on Lagrangian Trajectories" published on JAMES](https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024MS004848).
 
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