arcgis.com 的前十大競爭對手

esri.com

You have a right to opt out of any selling of your personal information. Esri does not sell your personal information, so we do not offer a choice to opt out.

mapbox.com

Mapbox is going to serve and protect your maps. For details, read our terms of service, service level agreement, privacy policy, & law enforcement guidelines.

openstreetmap.org

OpenStreetMap is a map of the world, created by people like you and free to use under an open license.

usgs.gov

Yes and no. It depends on which glaciers you are considering. Parts of the Antarctic Continent have had continuous glacier cover for perhaps as long as 20 million years. Other areas, such as valley glaciers of the Antarctic Peninsula and glaciers of the Transantarctic Mountains may date from the early Pleistocene. For Greenland, ice cores and related data suggest that all of southern Greenland and most of northern Greenland were ice-free during the last interglacial period, approximately 125,000 years ago. Then, climate was as much as 3-5o Fahrenheit warmer than the interglacial period we currently live in. Although the higher mountains of Alaska have hosted glaciers for as much as the past 4 million years, temperate glaciers in Alaska are generally much, much younger. Many formed as recently as the start of the Little Ice Age, approximately 700 years ago. Others may ...

iceinmyarea.org

Anonymous community tool to report and track ICE activity. Help protect undocumented immigrants with real-time safety alerts.

gis.stackexchange.com

Q&A for cartographers, geographers and GIS professionals

catalog.data.gov

The NREL PVDAQ is a large-scale time-series database containing system metadata and performance data from a variety of experimental PV sites and commercial public PV sites. The...