hummock


Also found in: Dictionary, Thesaurus, Acronyms, Wikipedia.

hummock

1. a hillock; knoll
2. a ridge or mound of ice in an ice field
3. Chiefly southern US a wooded area lying above the level of an adjacent marsh

Hummock

 

a pileup of fragments of ice floes on the ice cover of seas, rivers, and lakes. Hummocks are caused by the lateral pressure of ice fields on one another and on the shoreline and shoals, which results in fragmentation of the edges of the fields. Hummocks are most common in the East Siberian and Chukchi seas and in the open part of the Arctic Ocean, where their height sometimes exceeds 8–9 m (in coastal areas it may reach 15–20 m).

Among the forms of hummock development that are distinguished are ridges (in solid drifting ice), barriers (hummock ridges on the margin of the shore ice, occasionally resting on the bottom), standing floes (ropaks), and stamukhi (individual pile-ups on shoals). The degree of development of hummocks is measured on a five-point scale; 0 indicates a completely smooth ice sheet, and 5 means that the ice sheet is completely covered with hummocks.

hummock

[′həm·ək]
(ecology)
A rounded or conical knoll frequently formed of earth and covered with vegetation.
(geology)
A rounded or conical knoll, mound, hillock, or other small elevation, generally of equal dimensions and not ridgelike. Also known as hammock.
(hydrology)
A mound, hillock, or pile of broken floating ice, either fresh or weathered, that has been forced upward by pressure, as in an ice field or ice floe.
References in periodicals archive ?
In one instance, the wire was observed to cross a deep pool (3 m diameter) bounded by two tall hummocks (> 0.75 m high).
Broad-scale estimates of C[H.sub.4] flux from northern wetlands have been difficult to obtain because of the spatial variability in moisture created by microtopographic features such as hummocks and hollows, an important seasonal or temporal component that involves both changes in soil temperature as well as water table levels, and the role of different substrates in the soil for bacterial activity (Moore and Knowles 1990, Morrissey and Livingston 1992, Roulet et al.
One of the nests was in a moss clump of Brachythecium rivulare at the base of an ash tree and a hummock of skunk cabbage.
fuscum lawn (surrounded by an equally high peat surface), and hummock (about 1 [m.sup.2] xeric microsite protruding above the surrounding peat surface).
Francoeur and Pepin (1975, 1978) investigated the density and distribution of Formica dakotensis nests in spruce bogs in Quebec; Kannowski (1959) described the flight activities and colony-founding behavior of ants in Sphagnum bogs in Michigan; and Luken and Billings (1986) studied the effect of two species of ants on hummock dynamics in an Alaskan peat bog.
Suddenly I deep-banked to avoid a snow ridge line, then nearly collided with an ice-glazed hummock.
Talking to this scribe, Kashu Khan - an aged man who had encroached some space at Road No.4 of Bhains Colony by establishing a hummock for loading and offloading the buffalos - said the KMC had removed his 'Dhakka' (hummock called in local language) in the wake of anti-encroachment drive 'but alas, it did not even touch the weighbridge namely Dastgir Kanta illegally constructed on the government road just before his hummock.'
Ten feet of his backyard, including a grassy hummock and knobby crabapple trees (all crawling with poison ivy) went over the cliff like a carpet slipping off a clothesline.
The probability of lack of contact of the pipeline with hummock for some time period can be accepted as a design level of reliability and calculated as (Surkov, 2000):
The first time I slipped off a hummock, my left foot went into 4 inches of water.
When Fisher saw that the stranger 'had a gun in one hand and a bamboo stick in the other' and 'was wearing "ski" and was jumping about from one ice hummock to another in a marvellous manner', he knew that their suspicions were correct, and they all rushed down to greet him and 'cheered until we were hoarse'.
Each paired sampling set included the top of a hummock and its adjacent hollow.