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The Atmosphere of Venus
Earth has ample water in its oceans but very little carbon dioxide in its incredibly thin atmosphere. By contrast, Venus is very dry and its thick environment is generally filled with carbon dioxide. The unique atmospheres of both Venus and Earth had been derived at least in part from gases spewed forth, or outgassed, by using volcanoes. The gases that emanate from present-day volcanoes on Earth, such as Mount Saint Helens, are predominantly water vapor, carbon dioxide, and sulfur dioxide. These gases ought to consequently have been important parts of the true atmospheres of each Venus and Earth. Much of the water on both planets is also believed to have come from influences from comets.
In fact, water probably once dominated the Venusian atmosphere. Venus and Earth are similar in dimension and mass, so Venusian volcanoes may also have outgassed as much water vapor as on Earth, and each planet would have had about the identical quantity of comets strike their surfaces. Studies of how stars evolve advocate that the early Sun used to be solely about 70 percent as luminous as it is now, so the temperature in Venus’ early environment needs to have been quite a bit lower. Thus water vapor would have been capable to liquefy and form oceans on Venus. But if water vapor and carbon dioxide were once so frequent in the atmospheres of each Earth and Venus, what became of Earth’s carbon dioxide? And what happened to the water on Venus?
The answer to the first question is that carbon dioxide is still found in abundance on Earth, but now, instead of being in the form of atmospheric carbon dioxide, it is either dissolved in the oceans or chemically bound into carbonate rocks, such as the limestone and marble that formed in the oceans. If Earth grew to become as hot as Venus, a good deal of its carbon dioxide would be boiled out of the oceans and baked out of the crust. Our planet would soon strengthen a thick, oppressive carbon dioxide atmosphere a lot like that of Venus.
To reply the query about Venus’ lack of water, we ought to return to the early records of the planet. Just as on present-day Earth, the oceans of Venus constrained the amount of atmospheric carbon dioxide by means of dissolving it in the oceans and binding it in carbonate rocks. But being nearer to the Sun than Earth is, much of the liquid water on Venus would have vaporized to create a thick cowl of water vapor clouds. Since water vapor is a greenhouse gas, this humid atmosphere—perhaps denser than Earth’s present-day atmosphere, however, significantly less dense than the surroundings that envelop Venus today—would have successfully trapped heat from the Sun. At first, this would have had little effect on the oceans of Venus. Although the temperature would have climbed above 100° C, the boiling point of water at sea level on Earth, the added atmospheric pressure from water vapor would have saved the water in Venus' oceans in a liquid state.
This hot and humid kingdom of affairs might also have endured for a number of hundred million years. But as the Sun’s strength output slowly elevated over time, the temperature on Venus’ surface would eventually have risen above 374°C. Above this temperature, no matter the atmospheric pressure, Venus’ oceans would have begun to evaporate, and the introduced water vapor in the surroundings would have extended the greenhouse effect. This would have made the temperature even greater and prompted the oceans to evaporate faster, producing extra water vapor. That, in turn, would have similarly intensified the greenhouse impact and made the temperature climb higher still.
Once Venus’ oceans disappeared, so did the mechanism for disposing of carbon dioxide from the atmosphere. With no oceans to dissolve it, outgassed carbon dioxide started to accumulate in the atmosphere, intensifying the greenhouse effect even more. Temperatures ultimately became excessive ample to "bake out" any carbon dioxide that used to be trapped in carbonate rocks. This liberated carbon dioxide fashioned the thick atmosphere of present-day Venus. Over time, the rising temperatures would have leveled off, solar ultraviolet radiation having broken down atmospheric water vapor molecules into hydrogen and oxygen. With all the water vapor gone, the greenhouse effect would no longer have accelerated.
Reading Passage Vocabulary
Earth has ample water in its oceans but very little carbon dioxide in its incredibly thin atmosphere. By contrast, Venus is very dry and its thick environment is generally filled with carbon dioxide. The unique atmospheres of both Venus and Earth had been derived at least in part from gases spewed forth, or outgassed, by using volcanoes. The gases that emanate from present-day volcanoes on Earth, such as Mount Saint Helens, are predominantly water vapor, carbon dioxide, and sulfur dioxide. These gases ought to consequently have been important parts of the true atmospheres of each Venus and Earth. Much of the water on both planets is also believed to have come from influences from comets.
In fact, water probably once dominated the Venusian atmosphere. Venus and Earth are similar in dimension and mass, so Venusian volcanoes may also have outgassed as much water vapor as on Earth, and each planet would have had about the identical quantity of comets strike their surfaces. Studies of how stars evolve advocate that the early Sun used to be solely about 70 percent as luminous as it is now, so the temperature in Venus’ early environment needs to have been quite a bit lower. Thus water vapor would have been capable to liquefy and form oceans on Venus. But if water vapor and carbon dioxide were once so frequent in the atmospheres of each Earth and Venus, what became of Earth’s carbon dioxide? And what happened to the water on Venus?
The answer to the first question is that carbon dioxide is still found in abundance on Earth, but now, instead of being in the form of atmospheric carbon dioxide, it is either dissolved in the oceans or chemically bound into carbonate rocks, such as the limestone and marble that formed in the oceans. If Earth grew to become as hot as Venus, a good deal of its carbon dioxide would be boiled out of the oceans and baked out of the crust. Our planet would soon strengthen a thick, oppressive carbon dioxide atmosphere a lot like that of Venus.
To reply the query about Venus’ lack of water, we ought to return to the early records of the planet. Just as on present-day Earth, the oceans of Venus constrained the amount of atmospheric carbon dioxide by means of dissolving it in the oceans and binding it in carbonate rocks. But being nearer to the Sun than Earth is, much of the liquid water on Venus would have vaporized to create a thick cowl of water vapor clouds. Since water vapor is a greenhouse gas, this humid atmosphere—perhaps denser than Earth’s present-day atmosphere, however, significantly less dense than the surroundings that envelop Venus today—would have successfully trapped heat from the Sun. At first, this would have had little effect on the oceans of Venus. Although the temperature would have climbed above 100° C, the boiling point of water at sea level on Earth, the added atmospheric pressure from water vapor would have saved the water in Venus' oceans in a liquid state.
This hot and humid kingdom of affairs might also have endured for a number of hundred million years. But as the Sun’s strength output slowly elevated over time, the temperature on Venus’ surface would eventually have risen above 374°C. Above this temperature, no matter the atmospheric pressure, Venus’ oceans would have begun to evaporate, and the introduced water vapor in the surroundings would have extended the greenhouse effect. This would have made the temperature even greater and prompted the oceans to evaporate faster, producing extra water vapor. That, in turn, would have similarly intensified the greenhouse impact and made the temperature climb higher still.
Once Venus’ oceans disappeared, so did the mechanism for disposing of carbon dioxide from the atmosphere. With no oceans to dissolve it, outgassed carbon dioxide started to accumulate in the atmosphere, intensifying the greenhouse effect even more. Temperatures ultimately became excessive ample to "bake out" any carbon dioxide that used to be trapped in carbonate rocks. This liberated carbon dioxide fashioned the thick atmosphere of present-day Venus. Over time, the rising temperatures would have leveled off, solar ultraviolet radiation having broken down atmospheric water vapor molecules into hydrogen and oxygen. With all the water vapor gone, the greenhouse effect would no longer have accelerated.
IELTS Academic Reading Tips for Success
Tips to improve your reading speed
Keep in mind, having a slow reading speed makes skimming or scanning a reading passage more difficult. The process of quickly skimming through a reading passage for specific keywords or main ideas is a requirement for you to employ successful reading strategies to improve your IELTS reading score. In other words, skimming and scanning are critical skills to ensure you complete all questions in the allotted time frame.
IELTS Reading Strategies
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Step 1: Read questions first
One of the most common mistakes that candidates make when approaching the reading exam is reading every single word of the passages. Although you can practice for the exam by reading for pleasure, "reading blindly" (reading without any sense of what the questions will ask) will not do you any favors in the exam. Instead, it will hurt your chances for effectively managing your time and getting the best score.
The main reason to read the questions first is because the type of question may determine what you read in the passage or how you read it. For example, some question types will call for the "skimming" technique, while others may call for the "scanning" technique.It is important to answer a set of questions that are of the same question type. You'll need to determine which question type you want to tackle first. A good strategy would be to start with the easier question type and move on to more difficult question types later. The Easiest question types are the ones where you spend less time reading. For example, the Matching Heading question type is an easier one because you only need to find the heading that best describes the main idea of a paragraph. An example of a difficult question type would be Identifying Information. For this question type, you'll need to read each paragraph to find out if each statement is TRUE, FALSE, or NOT GIVEN according to the passage.
Here is a table that lists the difficulty levels for each question type. Use this table as a reference when choosing which question type you want to tackle first.
Difficulty level Question Type Easy Sentence Completion
Short answerMedium Matching Features
Multiple choice
Matching Headings
Summary, Table, Flow-Chart CompletionDifficult Matching Sentence Endings
Matching Information
Identifying Information (TRUE/FALSE/NOT GIVEN)
Identifying Viewer's claims (YES/NO/NOT GIVEN)
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Step 2: Read for an objective
After you've read the questions for the passage, you will be able to read for an objective. What does this mean? For example, if you come across a question that includes the year "1896", you can make a note of when this year comes up in the text, using it to answer the question later on. There are two reading techniques that will help you stay on track with reading for an objective. The first one, skimming, is best defined as reading fast in order to get the "gist", or general idea, or a passage. With this technique, you are not stopping for any unfamiliar words or looking for specific details. The second technique, scanning, is best defined as reading for specific information. With this technique, you are not reading for the overall gist, but rather, specific information. Notice how each of these techniques has a specific objective in mind. This will help you find information more quickly.
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Step 3: Take notes
As you're reading for an objective, you should also be making notes on the margins of the passage, placing stars next to key information, or underlining things that you believe will help you answer the various questions. This will make it easier for you to check back when you are asked certain things in the questions. Choose whichever note-taking system is right for you - just make sure you do it!
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Step 4: Answer wisely
After you've read the questions, read the passage, and have taken any appropriate notes, you you should have located the part of the text where you where you need to read carefully. Then just read carefully and think critically to determine the correct answer.
IELTS Reading Question Types
The IELTS reading test contains many different question types:
Matching Headings | IELTS Reading Lesson: Matching Headings |
Matching Information | IELTS Reading Lesson: Matching Information |
Matching Features | IELTS Reading Lesson: Matching Features |
Summary Completion | IELTS Reading Lesson: Summary Completion |
Identifying Information | IELTS Reading Lesson: Identifying Information |
Identifying Writer's claims | IELTS Reading Lesson: Identifying Writer's claims |
Multiple Choice | IELTS Reading Lesson: Multiple Choice |
Short Answer | IELTS Reading Lesson: Short Answer |
Match Sentence Ending | IELTS Reading Lesson: Match Sentence Ending |
Sentence Completion | IELTS Reading Lesson: Sentence Completion |
Table Completion | IELTS Reading Lesson: Table Completion |