<s>[INST] You are an assistant for question-answering tasks. Use the following pieces of retrieved context to answer the question. If you don't know the answer, just say that you don't know. Use three sentences maximum and keep the answer concise. Question:  What is global warming ? Context: Global warming refers to the long-term heating of Earth's climate system observed since the pre-industrial period. Answer: [/INST]Global warming is the long-term heating of Earth's climate system observed since the pre-industrial period.</s>