Category Earth Science

What conditions could help more parts of Earth host life?

Researchers find out an often overlooked key role played by the orbit of Jupiter on Earth.

Most planets have eccentric orbits. While circular orbits around a star would ensure that the distance between the star and the planet never changes, these eccentric orbits mean that the planets traverse around a star in an oval-shape. As a result, the planet would receive more heat when it goes closer to the star, affecting the planet’s climate.

Alternative solar system

Based on this knowledge and using detailed data from the solar system as we know it today, researchers from the University of California Riverside created an alternative solar system. In this hypothetical theoretical system, they were able to show that if Jupiter’s orbit were to become more eccentric, then it would lead to big changes in Earth’s orbit, thereby making the Earth more hospitable than it is currently.

This is because Jupiter in this theoretical system would push Earth’s orbit to be even more eccentric. As a result, parts of Earth would sometimes get closer to the sun. This would mean that even parts of Earth’s surface that are now sub-freezing will get warmer. In effect, the habitable range on the surface of the Earth would be increased.

Assumptions proven wrong

 The findings of this research, published in September in Astronomical Journal, go against two long-held scientific beliefs with respect to our solar system. One of these is that the current avatar of Earth is the best in terms of habitability. The second one is that changes to Jupiter’s orbit could only be bad for Earth.

Apart from upending these long-held assumptions, the researchers are looking to apply their findings in the search of exoplanets – habitable planets around other stars. While existing telescopes are adept at measuring a planet’s orbit, the same cannot be said about measuring a planet’s tilt towards or away from a star- another factor that could affect habitability.

The model developed in this research helps us better understand the impact of the biggest planet in our solar system, Jupiter, on Earth’s climate through time. Additionally, it also paves the way to find out how the movement of a giant planet is crucial in making predictions about habitability of planets in other systems.

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DO BACTERIA AND FUNGI SPEED UP WEATHERING?

When water collects in the cracks of a rock, it can freeze when temperatures drop. The ice expands and the pressure can split the rock. In cold, mountain regions, one can even hear gunshot-like cracks as rocks are split apart by frost.

A mechanical process, freeze-thaw weathering causes the ?joints?(cracks) in rocks to expand, which wedges parts of rocks apart. Because water expands by about 10% when it freezes, this creates outward pressure in rock joints, making the cracks larger.

Joints occur naturally in rocks as a result of their formation. Fractures that are not offset, joints do allow for the entry of water into rocks.

In climates where temperatures dip below freezing in the winter, moisture in the joints of rocks solidifies as ice. Over time, after several cycles of freezing and thawing, joints get large enough that bit of rock start to fall off in smaller pieces. This breakdown of rock happens faster at higher altitudes, where many freeze-thaw cycles can occur during the year.

Credit: Sciencing

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HOW DOES FROST BREAK UP ROCKS?

When water collects in the cracks of a rock, it can freeze when temperatures drop. The ice expands and the pressure can split the rock. In cold, mountain regions, one can even hear gunshot-like cracks as rocks are split apart by frost.

A mechanical process, freeze-thaw weathering causes the joints? (cracks) in rocks to expand, which wedges parts of rocks apart. Because water expands by about 10% when it freezes, this creates outward pressure in rock joints, making the cracks larger.

Joints occur naturally in rocks as a result of their formation. Fractures that are not offset, joints do allow for the entry of water into rocks.

In climates where temperatures dip below freezing in the winter, moisture in the joints of rocks solidifies as ice. Over time, after several cycles of freezing and thawing, joints get large enough that bit of rock start to fall off in smaller pieces. This breakdown of rock happens faster at higher altitudes, where many freeze-thaw cycles can occur during the year.

Credit: Sciencing

Picture Credit : Google 

IS THE ATMOSPHERE BUILT UP IN LAYERS?

Yes, the atmosphere has five layers. The lowest layer, closest to the surface of the Earth, is the troposphere. This is where weather is made, and most of the atmosphere’s gases are concentrated in it. Above it is the Stratosphere. No winds blow in this layer, nor are there any clouds. Beyond it lies the cold mesosphere, with very few gases. It is followed by the thermosphere, the thickest and hottest layer of the atmosphere, and lastly, the exosphere, on the edge of outer space.

Earth’s atmosphere is all around us. Most people take it for granted. Among other things, it shields us from radiation and prevents our precious water from evaporating into space. It keeps the planet warm and provides us with oxygen to breathe. In fact, the atmosphere makes Earth the livable, lovable home sweet home that it is.

The atmosphere extends from Earth’s surface to more than 10,000 kilometers (6,200 miles) above the planet. Those 10,000 kilometers are divided into five distinct layers. From the bottom layer to the top, the air in each has the same composition. But the higher up you go, the further apart those air molecules are.

Troposphere: Earth’s surface to between 8 and 14 kilometers (5 and 9 miles)

This lowest layer of the atmosphere starts at the ground and extends 14 kilometers (9 miles) up at the equator. That’s where it’s thickest. It’s thinnest above the poles, just 8 kilometers (5 miles) or so. The troposphere holds nearly all of Earth’s water vapor. It’s where most clouds ride the winds and where weather occurs. Water vapor and air constantly circulate in turbulent convection currents. Not surprisingly, the troposphere also is by far the densest layer. It contains as much as 80 percent of the mass of the whole atmosphere. The further up you go in this layer, the colder it gets.

Stratosphere: 14 to 64 km (9 to about 31 miles)

Unlike the troposphere, temperatures in this layer increase with elevation. The stratosphere is very dry, so clouds rarely form here. It also contains most of the atmosphere’s ozone, triplet molecules made from three oxygen atoms. At this elevation, ozone protects life on Earth from the sun’s harmful ultraviolet radiation. It’s a very stable layer, with little circulation. For that reason, commercial airlines tend to fly in the lower stratosphere to keep flights smooth. This lack of vertical movement also explains why stuff that gets into in the stratosphere tends to stay there for a long time. That “stuff” might include aerosol particles shot skyward by volcanic eruptions, and even smoke from wildfires. This layer also has accumulated pollutants, such as chlorofluorocarbons. Better known as CFCs, these chemicals can destroy the protective ozone layer, thinning it greatly. By the top of the stratosphere, called the stratopause, air is only a thousandth as dense as at Earth’s surface.

Mesosphere: 64 to 85 km (31 to 53 miles)

Scientists don’t know quite as much about this layer. It’s just harder to study. Airplanes and research balloons don’t operate this high and satellites orbit higher up. We do know that the mesosphere is where most meteors harmlessly burn up as they hurtle towards Earth.

The mesopause is also known as the Karman line. It’s named for the Hungarian-born physicist Theodore von Kármán. He was looking to determine the lower edge of what might constitute outer space. He set it at about 80 kilometers (50 miles) up.

The ionosphere is a zone of charged particles that extends from the upper stratosphere or lower mesosphere all the way to the exosphere. The ionosphere is able to reflect radio waves; this allows radio communications.

Thermosphere: 85 to 600 km (53 to 372 miles)

The next layer up is the thermosphere. It soaks up x-rays and ultraviolet energy from the sun, protecting those of us on the ground from these harmful rays. The ups and downs of that solar energy also make the thermosphere vary wildly in temperature. It can go from really cold to as hot as about 1,980 ºC (3,600 ºF) near the top. The sun’s varying energy output also causes the thickness of this layer to expand as it heats and to contract as it cools. With all the charged particles, the thermosphere is also home to those beautiful celestial light shows known as auroras. This layer’s top boundary is called the thermopause.

Exosphere: 600 to 10,000 km (372 to 6,200 miles)

The uppermost layer of Earth’s atmosphere is called the exosphere. Its lower boundary is known as the exobase. The exosphere has no firmly defined top. Instead, it just fades further out into space. Air molecules in this part of our atmosphere are so far apart that they rarely even collide with each other. Earth’s gravity still has a little pull here, but just enough to keep most of the sparse air molecules from drifting away. Still, some of those air molecules — tiny bits of our atmosphere — do float away, lost to Earth forever.

Credit: Science news for students

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What is the career in the field of Earth Sciences?

Our Earth is extremely fragile, and human activities are making it more vulnerable. One of the recent examples of the impact of indiscriminate development and climate change is the shocking collapse of a portion of the Nanda Devi glacier in Uttarakhand’s Chamoli district on February 7, 2021, and the ensuing floods that claimed many lives. The deadly disaster brings to light the need to rigorously study the impact of human activity on the environment. And that’s exactly what earth scientists do.

What is Earth Science?

Earth science is the study of the structure, composition, and evolution of the Earth, the life it supports, and the processes that govern the formation and behaviour of the Earth’s materials. It seeks to find answers to questions such as how ice moves, where the mineral resources are, and the rate of permafrost thaw. Understanding these phenomena is essential to the maintenance of life on the planet.

Different branches:

  • Glaciology: Glaciologists assess the impact of climate change, look for alternatives to sustain Earth’s depleting resources, and forecast avalanches.
  • Geology: Geologists study Earth and the processes that act on its materials. It also traces the history of the planet and its life forms since origin.
  • Hydrogeology: The study of water flow on and below the Earth’s surface and its chemistry.
  • Limnology: Limnology examines lake sediments to determine past climate and ecological environments.
  • Oceanography: The study of the ocean, including its water, boundaries and topography, types of currents, and marine biology.
  • Volcanology and Seismology: The scientific study of the dynamics of volcanoes and earthquakes.

What to study?

Universities in India and abroad offer a range of courses in Earth Sciences. You can pursue a Master of Science (M.Sc) and specialise in the field of your choice. A Ph.D is required to start working in the field.

Where: India

  • Wadia Institute of Himalayan Geology, Dehradun: Training and research programmes on Geomorphology and Environmental Geology. Geophysics, Petrology and Geochemistry
  • Indian Institute of Science Education and Research, Pune: Dual degree programme Bachelor of Science and Master of Science
  • Sharada University. Noida, and Pondicherry University: M.Sc in Environmental Sciences
  • Bharatiya Vidyapeeth, Insitute of Environment Education and Research. Punes M.Sc in Environment Science and Technology
  • Annamalai University, Cuddalore: M.Sc Earth Sciences and PG diplomas in Petroleum and Remote Sensing

Abroad

  • Utrecht University, the Netherlands, M.Sc Earth Surface and Water
  • University of Helsinki, Finland: M.Sc Geology and Geophysics
  • The University of Westent Australia: Master of Geographic Information Science
  • Massachusetts Institute of Technology, the U.S. M.SC Atmospheres, Oceans and Climate: M.Sc Geology, Geochemistry and Geobiology; Master of Environmental Policy and Planning

What are the job prospects?

Earth scientists primarily work in research organisations and environmental monitoring agencies.

These organisations could be in the private as well as the public sector.

Depending on your field of interest, you can also work with non-profit organisations and think-tanks on environment conservation and policy. If you have an academic bent of mind, then working in a university as a professor in the field of your choice could also suit you.

 

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What is GPS map?

This accurate, up-to-date map is created using digital technology. You can view GPS maps on your phone, tablet, or computer. They can tell you exactly where you are at any time. The coordinates and position as well as atomic time obtained by a terrestrial GPS receiver from GPS satellites orbiting Earth interact together to provide the digital mapping programming with points of origin in addition to the destination points needed to calculate distance. This information is then analyzed and compiled to create a map that provides the easiest and most efficient way to reach a destination.

More technically speaking, the device operates in the following manner:

  • GPS receivers collect data from at least four GPS satellites orbiting the Earth, calculating position in three dimensions.
  • The GPS receiver then utilizes position to provide GPS coordinates, or exact points of latitudinal and longitudinal direction from GPS satellites.
  • The points, or coordinates, output an accurate range between approximately “10-20 meters” of the actual location.
  • The beginning point, entered via GPS coordinates, and the ending point, (address or coordinates) input by the user, are then entered into the digital mapping software.
  • The mapping software outputs a real-time visual representation of the route. The map then moves along the path of the driver.
  • If the driver drifts from the designated route, the navigation system will use the current coordinates to recalculate a route to the destination location.

 

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