In surveying and geodesy, a datum is a reference system or an approximation of the Earth's surface against which positional measurements are made for computing locations. Horizontal datums are used for describing a point on the Earth 's surface, in latitude and longitude or another coordinate system.n approximate definition of sea level is the datum WGS 84, an ellipsoid, whereas a more accurate definition is Earth Gravitational Model 2008 (EGM2008), using at least 2,159 spherical harmonics.
A colorful garden variety, purple flowers and plants set off fiery colors found in the garden like red and orange while complementing green accent plants. Purple plants range in color from deep violet to pale lilac and lavender shades. Some purple flower types are perennials and have the ability to emerge every year for a constant source of color to the garden. Deciduous flowering vines with purple blooms showcase outdoor structures like pergolas, mailboxes and trellises for a showy display.
Purple Trailing Ice Plant Delosperma Cooperi Fast growing spreading succulent. It loves full sun in Arizona and is a great choice for color on a mound, draping over a pot, or any location in a desert or tropical landscape design.The Purple Ice Plant is a very drought resistant ground cover and is also cold hardy.