Hail—pieces of ice that form and fall from clouds instead of snow or rain—has always been a problem for farmers in some areas of the United States. Hail pellets can fall with great force and destroy crops in the field. Over the last few decades, a met

Essay topics:

Hail—pieces of ice that form and fall from clouds instead of snow or rain—has always been a problem for farmers in some areas of the United States. Hail pellets can fall with great force and destroy crops in the field. Over the last few decades, a method of reducing hail, called “cloud seeding,” has been tried. In cloud seeding, the chemical silver iodide is sprayed on storm clouds from an airplane. This makes the clouds produce harmless rain or snow instead of hail. Several pieces of evidence suggest that cloud seeding has been effective in protecting crops from hail.
Laboratory experiments
Experiments in the laboratory support the idea that cloud seeding is effective. Hail usually forms in water vapor that is close to the freezing point. However, when experimenters added silver iodide to cold water vapor in the laboratory, they often observed light snow forming instead of hail pellets.
Evidence from Asia
There is evidence about the effectiveness of cloud seeding from several countries around the world. In some Asian countries, for example, cloud seeding has been successfully used to control precipitation in urban areas. These positive results suggest that cloud seeding should also be effective in protecting fields and farms in the United States.
Local studies
A few local studies also support the value of cloud seeding. One study conducted in a farming region in the central United States, for example, directly monitored crop damage due to hail. The study found that in an area where cloud seeding was used there was reduced hail damage compared to previous years.

Now listen to part of a lecture on the topic you just read about.

It’s not clear that cloud seeding is all that effective and there are reasons to question each of the arguments you just read.

First, it may be true that under laboratory conditions, silver iodide creates snow instead of hail. However, in real life, silver iodide can actually prevent any precipitation at all from forming in the clouds—snow, rain, or hail. This is a bad thing, because if you seed all the clouds in areas where it doesn’t rain very often, you run the risk of causing a drought. In this case the crops simply get damaged for a different reason—lack of water.

Second, it’s not clear that the positive results with cloud seeding in Asia can be repeated in the United States. The reason is that cloud seeding in Asia was tried in urban areas—in cities. And cities tend to have a high level of air pollution—from car traffic, industry, etc. Surprisingly, pollution particles can create favorable conditions for cloud seeding, because they interact with clouds and the seeding chemicals. Such favorable conditions for cloud seeding may not occur in an unpolluted area. This means that the cloud seeding method that works in polluted cities may not work in unpolluted farming regions in the United States.

Third, the local study mentioned in the passage isn’t very convincing either. That’s because the study found that hail damage decreased not just in the area where the cloud seeding actually took place, but also in many of the neighboring areas to the east, south, and north of that area. So, the fact that the whole region was experiencing a reduced number of hailstorms that particular year makes it more likely that this was a result of natural variation in local weather and had nothing to do with cloud seeding.

Farmers from the United States tried a way called "cloud seeding" to reduce hail which can damage crops in the field, and the reading passage gives three plausible evidence to prove that it is able to protect crops effectively. However, the professor in the lecture states that all them are unconvincing.

First, the reading puts forward that the result of experiments made in the laboratory can support this idea. Scientist found that when they added silver iodide to the water vapor, light snow formed rather than hail pellets. The professor argues that even though the result of experiments is true, there is a more serious problem with this method. This substance can not only prevent the hail but also can stop forming snow and rain-that is it cause drought, which farmers do not want to see.

Moreover, the reading suggests that it was proved to control the pollution in some Asia cities effectively. However, this statement also has an enormous loophole: air pollutants are favorable to the cloud seeding; rather the unpolluted air do not have this consequence, which means it cannot be repeated in the American farm field.

Finally, the reading thinks some local research can support this idea; he uses an example of a study made in central America which claims that the number of hail damages is less than the past after using cloud seeding. The lecture opposes by contrasting the whole region with this specific place and argues that the reduction does not have a certain clear relationship with cloud seeding for it overlaps the whole area. The reason is the result of natural variation or local weather changing than using this method.

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2019-01-11 yang123 70 view
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Comments

Transition Words or Phrases used:
also, but, finally, first, however, if, moreover, so

Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments

Performance on Part of Speech:
To be verbs : 10.0 10.4613686534 96% => OK
Auxiliary verbs: 6.0 5.04856512141 119% => OK
Conjunction : 5.0 7.30242825607 68% => OK
Relative clauses : 14.0 12.0772626932 116% => OK
Pronoun: 25.0 22.412803532 112% => OK
Preposition: 25.0 30.3222958057 82% => OK
Nominalization: 7.0 5.01324503311 140% => OK

Performance on vocabulary words:
No of characters: 1390.0 1373.03311258 101% => OK
No of words: 277.0 270.72406181 102% => OK
Chars per words: 5.01805054152 5.08290768461 99% => OK
Fourth root words length: 4.07962216107 4.04702891845 101% => OK
Word Length SD: 2.46478673786 2.5805825403 96% => OK
Unique words: 161.0 145.348785872 111% => OK
Unique words percentage: 0.581227436823 0.540411800872 108% => OK
syllable_count: 419.4 419.366225166 100% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 3.0 3.25607064018 92% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.

Performance on sentences:
How many sentences: 11.0 13.0662251656 84% => Need more sentences. Double check the format of sentences, make sure there is a space between two sentences, or have enough periods. And also check the lengths of sentences, maybe they are too long.
Sentence length: 25.0 21.2450331126 118% => OK
Sentence length SD: 55.7989306453 49.2860985944 113% => OK
Chars per sentence: 126.363636364 110.228320801 115% => OK
Words per sentence: 25.1818181818 21.698381199 116% => OK
Discourse Markers: 4.72727272727 7.06452816374 67% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 0.0 4.19205298013 0% => OK
Sentences with positive sentiment : 7.0 4.33554083885 161% => OK
Sentences with negative sentiment : 3.0 4.45695364238 67% => OK
Sentences with neutral sentiment: 1.0 4.27373068433 23% => More facts, knowledge or examples wanted.
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.189367953683 0.272083759551 70% => OK
Sentence topic coherence: 0.065848336459 0.0996497079465 66% => OK
Sentence topic coherence SD: 0.057710638444 0.0662205650399 87% => OK
Paragraph topic coherence: 0.110839291881 0.162205337803 68% => OK
Paragraph topic coherence SD: 0.047489292136 0.0443174109184 107% => OK

Essay readability:
automated_readability_index: 14.8 13.3589403974 111% => OK
flesch_reading_ease: 54.56 53.8541721854 101% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 11.9 11.0289183223 108% => OK
coleman_liau_index: 12.13 12.2367328918 99% => OK
dale_chall_readability_score: 9.04 8.42419426049 107% => OK
difficult_words: 73.0 63.6247240618 115% => OK
linsear_write_formula: 11.0 10.7273730684 103% => OK
gunning_fog: 12.0 10.498013245 114% => OK
text_standard: 12.0 11.2008830022 107% => OK
What are above readability scores?

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Rates: 80.0 out of 100
Scores by essay e-grader: 24.0 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.