* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Day 10 - Ch. 5
Survey
Document related concepts
Large igneous province wikipedia , lookup
Schiehallion experiment wikipedia , lookup
Global Energy and Water Cycle Experiment wikipedia , lookup
Spherical Earth wikipedia , lookup
Post-glacial rebound wikipedia , lookup
History of geomagnetism wikipedia , lookup
Van Allen radiation belt wikipedia , lookup
History of geology wikipedia , lookup
History of climate change science wikipedia , lookup
Tectonic–climatic interaction wikipedia , lookup
Age of the Earth wikipedia , lookup
Transcript
Chapter 6: The Terrestrial Planets - Earth From the Earth, Venus appears as a white planet in the evening sky or the morning sky. From Mars, the Earth might appear as an “evening star” just after this sunset: (photo taken by a Rover on the Mars surface). Just after a sunset on Mars, the Earth appeared as a pale blue planet in the evening sky. A closer look reveals a planet ¾ -covered with liquid water Earth’s Atmosphere is layered. Convection heats the lower atmosphere, distributing heat from the ground. The Greenhouse Effect plays a major role in heating the Earth’s atmosphere. Factors include: Clouds Water vapor Agriculture City “heat islands” Carbon dioxide Methane CFC gases Dust and pollution Snow cover Desertification Global Warming is definitely occurring, but this may be due to several reasons. Global Warming may be due partly to increasing carbon dioxide levels which increase the Greenhouse effect . The data below is from ice cores, which have trapped air. Ice cores from Antarctica show the trends in carbon dioxide levels for the last 1000 years. x Ice cores from Antarctica show the trends in carbon dioxide levels for the last 800,000 years including four ice ages. x Increasing carbon dioxide levels have been measured on the Hawaiian volcano, Mauna Loa. This data is known as the Keeling curve (link). More data is available from Australia (link). Earth’s interior is revealed by seismology, the study of earthquakes. Layers are revealed: A layered object: Inner core Outer core Mantle Crust Hydrosphere Atmosphere Magnetosphere Observation of Seismic Waves due to earthquakes reveals the interior structure of the Earth Earth’s Interior The mantle is about 80% of the volume of the Earth. It is mostly a rocky material (basalt). The core is believed to be mostly iron and nickel, but could have many of the heavier elements. There is certainly some uranium and other radioactive elements which produce heat that keeps the core hot. High pressure causes the inner core to be a solid. The outer core is liquid. We will compare this structure with other planet’s structures. Global Plates move slowly – plate tectonics The motion at their boundaries causes earthquakes. Himalayas are due to colliding tectonic plates. Californian Fault (San Andreas fault) is where plates are slipping and cause earthquakes. Plate Drift causes many effects: earthquakes, rift valleys, mountain chains, volcanoes, mid-Atlantic ridge, etc. Earth’s Magnetosphere varies in size, depending on the solar wind. Van Allen Belts, named after James Van Allen of the Univ. of Iowa, who sent instruments up on early U.S. spacecraft. link The Aurora Borealis are due to charged particles trapped in the Earth’s magnetic field, causing air molecules to glow.