NATS 1840 Lecture : NATS 1840- Science.Tech&Enviro. LECTURE NOTES

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50-60 multiple choice questions: no penalty, worth the same, covers everything from beginning and more emphasis on second half (after mid- term stuff) Accurate measurements of co2 concentrations require an isolated location to avoid local anomalies. Atmospheric carbon dioxide measured at manua loa, hawaii. A 20% increase since 1960 is confirmed by other stations. Little evidence of any increase in water vapour. Changes in greenhouse gas concentrations may be of man-made (anthropogenic) origin: conversion of forests to crop fields, wood and fossil fuel burning; Antarctic ice core measurements suggest: co2 concentrations up by as much as 40% since 1750, methane concentrations may have doubled since 1800. Attributing the rise in carbon dioxide concentration to human activities unambiguously is challenging. Greenhouse gas concentrations, which play a dominant role in determining the planet"s climate, are rising. Hypothesis: global warming is primarily caused by an enhanced greenhouse effect due to rising atmospheric concentrations of greenhouse gases such as carbon dioxide and methane.