A Street Cat Named Bob is the autobiography of James Bowen's life on the street, and the story of the friend he find's in a cat he names Bob. I must admit Bob never stops amazing me in this book, he is so intelligent and loyal! I'd love to meet him myself and I can see why everyone who encounters Bob loves him, too.
The Silurian atmosphere shows a decline from carbon dioxide values of 1200 ppm in the Upper Ordovician. Budyko and others (1987) (see Fig. 8) indicated atmospheric oxygen declines from about 65 percent of PAL (Present Atmospheric Level) to about 35 percent of PAL in the Late Silurian.
Atmosphere of Earth. The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention, and reducing temperature extremes between day and night. By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.