• Integrated Taxonomic Information System
Here you will find authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
• Comparative Climate Data for the US
From Cornell's Northeast Regional Climate Center
• ECOLEX: the gateway to environmental law
The ECOLEX database includes information on treaties, international soft-law and other non-binding policy and technical guidance documents, national legislation, judicial decisions, and law and policy literature.
• EPA
US Environmental Protection Agency.
• IRIS: Incorporated Research Institutions for Seismology
Source for seismic data and other information.
• NASA: Global Climate Change
Data, images, and explanations on the mechanism and effects of climate change.
• National Climatic Data Center
Climate data from NOAA.
• USGS: Publications
Maps, aerial photographs, reports and more from the US Geological Survey.
• Encyclopedia of Life
The Encyclopedia of Life (EOL) is an ambitious project to organize and make available via the Internet virtually all information about life present on Earth. At its heart lies a series of Web sites—one for each of the approximately 1.8 million known species—that provide the entry points to this vast array of knowledge.
• Tree of Life
The Tree of Life Web Project is a collection of information about biodiversity compiled collaboratively by hundreds of expert and amateur contributors. Its goal is to contain a page with pictures, text, and other information for every species and for each group of organisms, living or extinct.
• Crop Index
Crops are listed alphabetically by genus and common name.
• Weed Identification
Key for identifying weeds species.
• USDA PLANTS Database
Standardized information about the vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories.
• CalPhotos
A collection of 359,733 photos of plants, animals, fossils, people, and landscapes from around the world.
• Common Trees of Pennsylvania (PDF)
This selection of 57 native, and 5 introduced trees is organized according to leaf shape and arrangement. Each tree is identified by popular name familiar to Pennsylvanians and its complete scientific name.