How Frosts, Freezes, and Hard Freezes Differ

How Frosts, Freezes, and Hard Freezes Differ Just as  the sprouting of tender green leaves is considered one of  the  first signs of spring,  the first frost of the cool season signals that fall has officially settled in  and that  winter isnt far behind. How Frost Forms Look for frost to form when these atmospheric conditions are present: clear nighttime sky conditions,at or below freezing air temperatures at the surface, andcalm winds (speeds less than 5 mph (1.6 km/h)). Clear skies and calm winds allow for daytime heating to escape the Earths surface. This heat out into the upper atmosphere and outer space. Whats known as a temperature inversion layer forms (temperatures increase rather than decrease as one travels upward in the air), and allows cold air to settle near the ground. As the ground temperatures cool to below freezing, what water vapor resides in the air ices up onto exposed surfaces thus forming frost. The terms frost  and freeze  are usually  mentioned together, however,  they describe two very  different happenings. Freezes Imply Lows Near 32 F A freeze means that widespread temperatures are expected to fall to or below the freezing mark (32  °F). A hard freeze implies that widespread temperatures are forecast to fall below freezing (most NWS offices use 28  °F as the threshold criteria) for long enough to seriously damage or kill seasonal vegetation. For this reason, hard freezes have earned the monicker killing frosts. A hard freeze usually occurs when a cold air mass moves into an area and brings temperatures of  32 °F or below. This  freezing cold air is often blown by winds, or  advected,  into an area, and may, therefore, be associated with light or variable wind speeds.   Frosts Imply Lows Near 32 F and Moist Ground Air Frost, on the other hand, has to do with  the formation of ice crystals on the ground and  on other surfaces. It occurs  in the absence of wind, and the  freezing  temperatures are the result of radiational cooling.  Whereas freezes have to do with air temperature alone, any weather alert having to do with frost not only implies that temperatures are expected to be 33 to 36  °F, but also that the amount of moisture residing in the air at these temperatures is adequate for frost formation near the surface.  Ã‚   Can a Freeze Occur Without Frost Forming? Yes, freezes can happen even if a frost doesnt. This seems odd since it takes colder temperatures (at least 32 degrees) to get a freeze. It seems like youd get a frost (which requires temperatures of 33 to 36 degrees) first. It would make sense that moisture would frost before freezing except that frost is less likely to form when the dew point temperature falls below the mid-20s. This is because, at such cold temperatures, there just isnt enough moisture in the air for significant frost formation despite the fact that cold enough temperatures are in place to support it. Frost Freeze Weather Safety The majority of individuals dont notice frost, except when it forms on their  car windows  and  delays their morning departure by several  minutes time. However, agriculturists and farmers consider  it is a critical weather event. This is because  most plants (except a few varieties that  actually need a hard freeze to coax seeds into germination)  are extremely sensitive to it. A frost too early,  or too late,  in the growing season can result in crop failure and a shortage of food supply. There are a number of ways to protect against frost damage, including: Cover  plants. When plants are covered, frost can settle on a barrier rather than on the vegetation directly. For this reason, plants not in direct contact with the covering material have the highest level of protection. Woven fabrics, such as sheets, work best and can offer 2 ° to 5 °F of added warmth. Potted plants should be covered or brought indoors.Irrigate  the soil and plant leaves  before the frost arrives.  This might sound strange considering water will freeze when the  temperature drops, but rest assured there is a method to this madness.  Moist soil is capable of holding up to four times more heat than dry soil. Likewise, if fruit trees have begun their yield, spraying the outside skin with water can actually help keep internal temperatures above freezing by allow the outside to freeze and create an insulating barrier.Keep plants watered to fight off drying from cold winds.Bring pets indoors whenever extreme cold is expected.Cover exposed pipes and outdoor faucets to discourage freezing. When to Expect Your First Frost/Freeze To find the average date of the first fall (and last spring) frost for your area, use this  frost and freeze data product, courtesy of the  National Climatic Data Center.  (To use, choose your state, then locate the city nearest you.)

Definition and Examples of Person in English Grammar

Definition and Examples of Person in English Grammar In English grammar, the category of person  identifies the relationship between a subject and its verb, showing whether the subject is speaking about itself (first personI or we); being spoken to (second personyou); or being spoken about (third personhe, she, it, or they). Also called grammatical person. Personal pronouns are so called because they are the pronouns to which the grammatical system of person applies. Reflexive pronouns, intensive pronouns, and possessive determiners also show distinctions in person. Examples and Observations A widely attested type of verbal inflection in human language involves persona category that typically distinguishes among the first person (the speaker), the second person (the addressee), and the third person (anyone else). In many languages, the verb is marked for both person and number (singular or plural) of the subject. When one category is inflected for properties (such as person and number) of another, the first category is said to agree with the second. . . .Modern English has a [comparatively] impoverished system of person and number agreement in the verb, and an inflectional affix is used only for the third person singular in the non-past tense.  (William OGrady, et al. Contemporary Linguistics: An Introduction. Bedford, 2001)I amYou areWe are Australian.(B. Woodley and D. Newton, I Am Australian)I am he as you are he as you are me and we are all together.(John Lennon and Paul McCartney, I Am the Walrus) The Three Persons in English (present tense) First person I see great things in baseball.(Walt Whitman)We see things as we are.(Leo Rosten) Second person You see things, and you say Why?(George Bernard Shaw) Third person She sees more hospices and sink estates than most people.(Prince Andrew)The traveler sees what he sees; the tourist sees what he has come to see.(G.K. Chesterton)[M]urder is always a mistake. One should never do anything that one cannot talk about after dinner.(Oscar Wilde, The Picture of Dorian Gray, 1890)Love is not blind: it sees more, not less.(Julius Gordon)They see me as some sort of pathetic character.(Mike Tyson) The Forms of Be Be is unique among English verbs in having three distinctive person forms in the present tense (am, is, are) and two in the past tense (was, were). Other verbs have a distinctive form only for the third person singular of the present tense (e.g., has, does, wants, etc., as opposed to have, do, want, etc.). (Bas Aarts, Sylvia Chalker, and Edmund Weiner, The Oxford Dictionary of English Grammar, 2nd ed. Oxford University Press, 2014) Etymology From the Latin persona, mask