This National Aeronautics and Space Administration (NASA) web site allows users to determine the total column ozone amount over a particular location for most dates between November, 1978 and December, 1994 and from August, 1996 to today. Users simply enter the ozone measuring date or instrument - Meteor 3, Nimbus 7, ADEOS, Earth Probe - and the latitude and longitude of the location of concern, and ... Full description.

This guide attempts to list all of the world's countries with a description of the local time in a region. Areas are grouped in a hierarchy by continent (region), country, and location. With each selection, information is given on geographical location; current local time, the current observed time, and the dates during which Daylight Savings Time is observed. Geographical locations are listed in ... Full description.

The Washington State University Tree Fruit Research and Extension Center provides a calculator for estimating water use by plants or pET (potential evapotranspiration). Water use varies widely from plant to plant, so estimates are usually first derived for a single situation, such as grass, and then adapted for other plants. The calculator uses the Penman method to estimate daily pET in inches of ... Full description.

This is a tool for converting degrees, minutes and seconds of latitude or longitude into decimal degrees, and vice-versa. It also gives the conversion formula, so users can try it themselves. Full description.

This calculation tool aids in area, length, circle, pressure, speed, temperature, time, volume, and weight conversions. Values are shown in Metric and British units, as well as old Russian, Nautical, Astronomical and others, making this a very comprehensive tool. Full description.

This web-tool calculates the great circle distance between two points on the Earth's surface. Users enter the latitude and longitude of two locations in degrees, minutes, and seconds, and the tool calculates the distance in kilometers and miles between the two points. Full description.

This website is the official time clock for the United States. Users choose from a variety of time zones (Marshall, Micronesia, Palau, Guam, Samoan, Hawaiian, Alaskan, Pacific, Mountain, Central, Eastern, Atlantic or UTC) and view the current time in that zone along with a map showing day and night across the world. A world time zone map is included for reference. Links are provided to other time-related ... Full description.

SunAngle is an on-line tool that calculates solar angles and related information for a given location, date, and time. It computes the declination of the Sun, sunrise and sunset times, azimuth of the Sun, solar time and more. Complete instructions and definitions of variables are included. Full description.

This website provides calculation tools for conversions of length, area, and degrees to radians. Map conversions include a map scale calculator, and conversions from degrees, minutes, and seconds to decimal degrees (and vice-versa). Full description.

This applet allows users to see what the elevation, noon elevation, and azimuth of the Sun is for specific locations (requested by city or latitude and longitude) and time zone for the current date. This program also shows how long the Sun will be above or below the horizon for the current date and the location the user chooses. Full description.