This report, together with accompanying files embedded as links, documents the methods, assumptions, scenarios, and sensitivities developed so far in the Net-Zero Brazil project. An overall summary
description of the project is available in the Institutional Document [1]. The goal of this report is to
communicate as transparently as possible the foundations of the multiple models underlying the NZB
User Platform (accessible at https://netzero.eco.br). The Modeling framework (Section 2) provides an
overview of each of the models that work in an integrated fashion on the Platform. This is followed
by Section 3, Model components and formulation, describing details regarding key design elements
of each model, as well as key input assumptions and datasets. The final section, Scenario building
(Section 4), explains each of the current 39 variables included in the Platform that a user may vary
to create their own scenarios. None of the resulting scenarios should be taken as predictions of
the future. Rather, scenarios are designed to help decision makers see more clearly how transition
pathways would need to be shaped to achieve desired objectives.

Finally, this is the first edition of the MASS document, and the team will update it on a regular basis as
the capabilities of the NZB models and Platform are improved and enhanced. Comments, suggestions,
and criticism from readers are welcome and will help identify necessary improvements.