| Term No. | Term Name | Term Description |
| 3783 | I-beam bridge | A small bridge consisting of a floor supported on I-beams...... |
| 9322 | Ice Cap | A dome-shaped ice mass covering a highland area that is considerably smaller in extent than ice sheets...... |
| 739 | Ice cover | Ice on the water surface of a lake or stream...... |
| 740 | Ice fringe | Ice deposit of moisture, not hoarfrost, exuded from stems of plants...... |
| 749 | Ice gorge, or Ice jam | A temporary dam that restricts flow. Caused by a stationary accumulation of fragmented ice or frazil...... |
| 7958 | Ice jam flood | An accumulation of broken river ice lodged in a narrow part of the river channel. It frequently produces local floods during a spring breakup, or floo..... |
| 2631 | Ice pressure | Pressure produced by ice due to its thermal expansion and by wind drag. Its value is generally taken from empirical curves developed from field and la..... |
| 9323 | Ice Shelf | A floating ice sheet of considerable thickness attached to a coast (usually of great horizontal extent with a level or gently undulating surface); oft..... |
| 744 | Ice storm | Storm characterized by occurrence of a glaze...... |
| 8538 | Iconic models, or Physical models | A physical replica of the real system on a reduced scale...... |
| 4614 | Ideal irrigation interval | Interval corresponding to irrigations meeting the actual requirements of the crop without shortages or excesses of water...... |
| 8600 | Identification problem, or Inverse problem | Problems involving determination of parameters that govern the response of a system...... |
| 5466 | Igneous magma | The molten fluids and gaseous fractions generated within the earth, from which igneous rocks are considered to have been derived by crystallization or..... |
| 5465 | Igneous rocks | Rock masses formed by the solidification of magma injected into the earth`s surface, or extruded on its surface...... |
| 1618 | Illuvial horizon | A soil layer or horizon in which the material carried on an overlying layer (eluvial horizon) has been precipitated from the solution or deposited fro..... |
| 6296 | Image | Recorded representation of an object produced by optical, electro-optical, optical-mechanical, or electronic means...... |
| 6297 | Image enhancement | Manipulation of image density or colour to allow certain features of the image to be seen more easily...... |
| 8178 | Image File | A file containing an image...... |
| 1811 | Imbibation moisture, or Water of imbibation | The moisture associated with soil colloidal material...... |
| 1598 | Immature soil | A soil with indistinct or only slightly developed horizons because of the relatively short time it has been subjected to the various soil-forming proc..... |
| 7114 | Immission | The reception of pollution from a remote source...... |
| 3059 | Impact | The striking together of two or more solid bodies or streams of fluid resulting in energy loss or more accurately, energy transformation...... |
| 6620 | Impact indicator | An environmental element or parameter that provides a qualitative measure of a human or natural activity...... |
| 3060 | Impact loss | The head lost as a result of the impact of particles of water; included in and scarcely distinguishable from eddy loss...... |
| 3061 | Impact pressure | The pressure acting at the forward stagnation point of a body, such as a Pitot tube, placed in liquid current. Impact pressure may be measured from an..... |
