terra0project / Two-Degrees

'Two Degrees' NFT code for Sotheby's 'Natively Digital: A Curated NTF Sale'

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  |_|   \_/\_/ \___/  |___/ \___| \__, ||_|  \___|\___|/__/
                                  |___/

This repo contains all of the code making up 'Two Degrees', a single NFT created for Sotheby's 'Natively Digital: A Curated NTF Sale' exhibition and auction.

A full write-up of the conceptual approach behind the project, plus a technical overview, can be found here.

Smart Contracts

There are two main smart contracts: an ERC721 Token, and a custom Oracle contract.

• TemperatureOracle.sol stores the average annual temperature rise as decided by NASA in their annual report, which can be updated by the o-address, an automated event listener running on a server. When this value crosses the threshold of 2 degrees centigrade, the token is able to be burned by anyone who wants to call the token contract's burn() function and do so.

• TemperatureToken implements a standard ERC721 interface using most OpenZeppelin functions. There is a small custom ACL which allows the TemperatureOracle contract to burn the minted token if the annual average temperature increase is > 2 degrees Celsius.