Looking at climate change over 4.6 billion years, the answer is not simple Hand drawn on World Meteorological Day Looking at climate change over 4.6 billion years, the answer is not simple Hand drawn on World Meteorological Day Looking at climate change over 4.6 billion years, the answer is not simple Hand drawn on World Meteorological Day Looking at climate change over 4.6 billion years, the answer is not simple Hand drawn on World Meteorological Day Transferred from: China Meteorological Administration