Exploring Planet Earth: A Portrait of Our Home
Earth | A series on Earth By Academic Block
Overview
Planet Earth, our celestial home, is a remarkable sphere that teems with life, diversity, and natural wonders. From the vast oceans that cover more than two-thirds of its surface to the towering mountain ranges and intricate ecosystems, Earth is a dynamic and complex planet that has fascinated scientists, explorers, and nature enthusiasts for centuries. In this article by Academic Block, we will embark on a journey to explore the geological, ecological, and atmospheric wonders of our planet, shedding light on the incredible forces and processes that have shaped Earth into the vibrant and interconnected world we know today.
Position of Earth in the solar system
The mass of the third planet from the sun, Earth is approximately 5.972 × 1024 kilograms. Earth's average distance from the Sun, known as astronomical unit (AU), is approximately 149.6 million kilometers (about 93 million miles). This distance also serves as a fundamental unit of measurement for distances within our solar system.
Earth's orbital position within the habitable zone, also known as the Goldilocks zone, is a defining factor that makes it a haven for life. This region, neither too close nor too far from the Sun, allows Earth to maintain a stable climate where liquid water can exist on its surface—a fundamental prerequisite for life as we know it.
Comparatively, Mercury and Venus, the innermost planets, suffer extreme conditions due to their proximity to the Sun. Mercury faces scorching daytime temperatures and freezing nights, while Venus experiences a runaway greenhouse effect that has led to surface temperatures hot enough to melt lead, rendering both planets inhospitable.
Earth takes approximately 23 hours, 56 minutes, and 4 seconds to complete one full rotation on its axis. This period is known as a sidereal day. However, when we measure a day in the context of our daily lives, we often refer to a "solar day" or simply a "day," which is slightly longer than a sidereal day. A solar day is the time it takes for Earth to rotate once on its axis so that the Sun appears in the same position in the sky as seen from a specific location on Earth. It is approximately 24 hours long. A year on Earth, also known as an "Earth year," is defined by the time it takes for our planet to complete one orbit around the Sun. An Earth year is approximately 365.25 days long, which is why we have leap years (with an extra day, February 29) every four years to account for the extra fraction of a day. This adjustment keeps our calendar synchronized with the Earth's orbit around the Sun.
Protective Magnetic Field
Earth boasts a robust magnetic field generated by its molten iron core. This magnetic field extends far beyond the planet's surface and forms a protective shield known as the magnetosphere. The magnetosphere is a complex and dynamic magnetic field that envelops our planet, extending far into space. It serves as Earth's protective shield against the relentless onslaught of solar radiation and cosmic particles, deflecting and redirecting these potentially harmful elements away from our atmosphere and surface.
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Formation and Structure Earth's magnetosphere is primarily generated by the planet's molten iron core, where the motion of the liquid metal creates electrical currents that produce a magnetic field. This field is aligned roughly with Earth's rotational axis but is not perfectly symmetrical, resulting in the magnetic poles being offset from the geographic poles. The magnetosphere has several distinct regions, including the magnetosheath, magnetotail, and bow shock, each with its own unique characteristics and interactions with incoming solar wind.
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Protecting Earth's Atmosphere The magnetosphere's primary role is to shield Earth's atmosphere from the erosive effects of solar wind, which consists of charged particles (mostly electrons and protons) streaming from the Sun. When these particles approach Earth, they are deflected by the magnetosphere, preventing them from stripping away our atmosphere and water molecules. This process has been crucial in maintaining the conditions necessary for life on our planet over geological timescales. Mars, for instance, lacks a strong magnetic field, which has resulted in the loss of much of its atmosphere over time. This loss of atmosphere has made Mars inhospitable for life as we know it.
Earth's Moons: The Stabilizer
Earth's moon, often simply referred to as "the Moon," serves as a stabilizing influence on our planet. It helps maintain Earth's axial tilt, which is responsible for the relative stability of our seasons. The Moon's gravitational pull also gives rise to ocean tides, influencing coastal ecosystems and nutrient cycles.
In contrast, most of the other planets in our solar system either lack moons or have moons that are significantly smaller in comparison. The presence of our Moon has played a crucial role in shaping Earth's climate, tides, and the evolution of life on our planet. To learn more about the moon, you can read article by academic block, specifically dedicated to the wonders of the Moon.
Geological Marvels of Earth
1. Plate Tectonics: Earth's Shifting Crust
At the heart of Earth's geological dynamics lies the theory of plate tectonics. This groundbreaking theory, proposed in the mid-20th century, explains how Earth's lithosphere is divided into several large and small tectonic plates that float on the semi-fluid asthenosphere beneath them. These plates constantly move, collide, pull apart, and slide past one another, giving rise to earthquakes, volcanic eruptions, and the formation of mountains and ocean basins. Plate tectonics has revolutionized our understanding of Earth's geology and continues to shape our planet's landscape.
2. Mountain Building: The Rise of Majestic Peaks
Mountains are among Earth's most striking features, and they come in various forms, from towering giants like the Himalayas to underwater mountain ranges known as mid-ocean ridges. Mountain formation results from the intense collision of tectonic plates, causing the Earth's crust to fold, uplift, and create vast elevations. These geological wonders play critical roles in shaping climate patterns, water distribution, and biodiversity.
3. Volcanoes: Earth's Fiery Vents
Volcanoes are the Earth's vents to its molten interior. They erupt when magma, gases, and molten rock from the Earth's mantle force their way to the surface. Volcanic eruptions can be destructive, but they also contribute to the formation of new landforms, enriching the soil and supporting unique ecosystems. The Ring of Fire, a horseshoe-shaped zone encircling the Pacific Ocean, is home to a significant portion of the world's active volcanoes.
Wonders of Earth's Oceans:
1. Oceanography: Exploring Earth's Aquatic Realms
Earth's oceans cover approximately 71% of its surface and contain a wealth of mysteries waiting to be unveiled. Oceanography, the scientific study of the oceans, has revealed a myriad of fascinating phenomena, including ocean currents, underwater ecosystems, and the deep-sea trenches that plunge to unfathomable depths. Oceans play a crucial role in regulating the planet's climate, serving as vast heat reservoirs and carbon sinks.
2. Coral Reefs: The Rainforests of the Sea
Coral reefs are some of the most diverse and productive ecosystems on Earth. Composed of living organisms called coral polyps, these underwater marvels provide habitat for countless marine species. However, coral reefs are facing threats from climate change, ocean acidification, overfishing, and pollution, making their conservation a global priority.
3. The Great Ocean Conveyor Belt
The global ocean circulation system, often referred to as the "Great Ocean Conveyor Belt," plays a pivotal role in regulating Earth's climate. This vast system circulates warm surface waters from the equator to the poles and cold, deep waters back toward the equator. Disruptions in this circulation can have profound effects on climate patterns, with potential consequences for regions worldwide.
Exploring Earth's Atmosphere
1. The Atmosphere: Our Invisible Shield
Earth's atmosphere is a vital component of the planet, providing the air we breathe and regulating temperatures. It consists of several layers, including the troposphere, where weather occurs, and the stratosphere, where the ozone layer shields us from harmful ultraviolet (UV) radiation. The study of atmospheric science helps us understand weather patterns, climate change, and the impact of human activities on our atmosphere.
Earth's atmosphere is composed of a mixture of gases, with varying concentrations. The primary components of Earth's atmosphere, along with their approximate percentages by volume, are as follows:
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Nitrogen (N2): Nitrogen is the most abundant gas in Earth's atmosphere, making up approximately 78% of the total volume.
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Oxygen (O2): Oxygen is the second most abundant gas in the atmosphere, constituting approximately 21% of the total volume. It is essential for respiration and combustion.
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Argon (Ar): Argon is a noble gas that makes up about 0.93% of the atmosphere by volume.
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Carbon Dioxide (CO2): Carbon dioxide is a crucial greenhouse gas, representing approximately 0.04% of the atmosphere. Its concentration has been increasing due to human activities, particularly the burning of fossil fuels.
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Other Gases: These are traces of other noble gases, each present in very small amounts in the atmosphere, with concentrations on the order of parts per million (ppm). Namely, Neon (Ne), Helium (He), Krypton (Kr), and Xenon (Xe).
It's important to note that the composition of the atmosphere can vary slightly with altitude, location, and over geological time scales. Human activities, such as industrial processes and the burning of fossil fuels, have also led to changes in the concentrations of certain gases, particularly carbon dioxide, which has been on the rise due to anthropogenic activities and is a key driver of climate change.
2. Weather Phenomena: From Thunderstorms to Hurricanes
Earth's atmosphere is a dynamic and ever-changing system that produces a wide range of weather phenomena. Thunderstorms, tornadoes, and hurricanes are among the most powerful and awe-inspiring atmospheric events. They result from complex interactions between air masses, moisture, and temperature gradients and can have both destructive and beneficial effects on ecosystems and regions.
3. Climate Change: Earth's Greatest Challenge
Climate change, driven by human activities such as burning fossil fuels and deforestation, poses one of the most significant challenges to our planet. The rise in greenhouse gases, such as carbon dioxide, traps heat in the atmosphere, leading to global warming and altered climate patterns. The consequences of climate change include rising sea levels, extreme weather events, and disruptions to ecosystems and agriculture.
Earth’s extreme Hot and Cold
Earth experiences a wide range of temperatures due to its varying climates and geographical features. The extreme temperatures on Earth can be categorized into the following:
1. Extreme Cold Temperatures:
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Antarctica: The coldest temperature ever recorded on Earth was at the Soviet Vostok Station in Antarctica on July 21, 1983, when the temperature plummeted to -128.6 degrees Fahrenheit (-89.2 degrees Celsius).
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Siberia Russia: Regions in Siberia, particularly in the northeastern part, often experience extreme cold during the winter months. Temperatures can drop well below -40 degrees Fahrenheit (-40 degrees Celsius) in some areas.
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Greenland: Greenland, the world's largest island, can experience extremely cold temperatures, with winter lows in some areas reaching -40 degrees Fahrenheit (-40 degrees Celsius).
2. Extreme Hot Temperatures:
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Death Valley, USA: Located in California, Death Valley is one of the hottest places on Earth. The highest air temperature ever recorded on earth was 134 degrees Fahrenheit (56.7 degrees Celsius) in Furnace Creek Ranch on July 10, 1913.
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Kuwait and Iraq: These Middle Eastern countries often experience extreme heat during the summer months. The highest reliably recorded temperature in modern times was 129.2 degrees Fahrenheit (54 degrees Celsius) in Kuwait in 2016.
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Iran: Cities like Ahvaz in Iran have experienced scorching temperatures, with summer highs regularly exceeding 120 degrees Fahrenheit (49 degrees Celsius).
It's important to note that these extreme temperatures represent outliers in specific regions and are not representative of the average temperatures experienced globally. Most of Earth's surface experiences more moderate temperature ranges, and variations in temperature are influenced by factors such as latitude, elevation, proximity to bodies of water, and prevailing weather patterns.
Biodiversity: Earth's Web of Life
Earth is home to an astounding array of life forms, from the tiniest microorganisms to the largest mammals. Biodiversity, the variety of species and ecosystems on Earth, sustains the planet's health and resilience. However, human activities, such as habitat destruction and overexploitation of resources, have led to a global decline in biodiversity, raising concerns about the stability of ecosystems and the services they provide.
1. Rainforests: Lungs of the Earth
Tropical rainforests are among the most biologically diverse and ecologically vital ecosystems on Earth. They play a crucial role in regulating climate, storing carbon, and providing habitat for countless species. Deforestation, primarily for agriculture and logging, threatens these invaluable ecosystems and exacerbates climate change.
2. Conservation Efforts: Protecting Earth's Treasures
Conservation organizations, scientists, and governments are working together to protect Earth's biodiversity and ecosystems. Initiatives include the creation of protected areas, reforestation efforts, and sustainable resource management practices. These endeavors aim to safeguard the planet's natural heritage for future generations.
Final Words
Planet Earth is a dynamic sphere of wonder and complexity, shaped by geological forces, sustained by interconnected ecosystems, and influenced by a delicate atmospheric balance. Understanding the intricacies of our planet's geology, oceans, atmosphere, and biodiversity is not only a scientific endeavor but also a call to action for responsible stewardship. As we continue to explore and appreciate the beauty and complexity of Earth, we must also strive to protect and preserve it for the well-being of all living creatures and future generations. Our planet is a precious gem in the vastness of the cosmos, and it is our duty to cherish and protect it.
This article by Academic Block is based on thoroughly researched scientific literature. We hope you will find this information on Earth useful and interesting. Please comment below, your suggestions and criticism help us in improving our articles. Thanks for reading.
This Article will answer your questions like:
Earth is the third planet from the Sun in the Solar System and the only known celestial body to support life. It is an oblate spheroid with a complex biosphere, hydrosphere, and atmosphere. Earth has diverse climates and ecosystems, and its geological and biological processes interact to sustain life.
Earth's diameter is approximately 12,742 kilometers (7,918 miles). This measurement varies slightly due to its equatorial bulge, with the equatorial diameter being about 43 kilometers (27 miles) larger than the polar diameter due to its oblate spheroid shape.
Earth is about 149.6 million kilometers (93 million miles) from the Sun on average, a distance known as an astronomical unit (AU). This distance varies slightly due to Earth's elliptical orbit, ranging from about 147.1 million kilometers (91.4 million miles) at perihelion to 152.1 million kilometers (94.5 million miles) at aphelion.
Earth's atmosphere is composed primarily of nitrogen (78%) and oxygen (21%), with trace amounts of argon, carbon dioxide, neon, and other gases. It also contains water vapor and various pollutants. This composition supports life, regulates temperature, and protects the planet from harmful solar radiation.
Earth's atmosphere protects life by absorbing and scattering ultraviolet (UV) radiation from the Sun, reducing harmful radiation that reaches the surface. It also stabilizes temperatures through the greenhouse effect, contains essential gases like oxygen for respiration, and provides a medium for weather and climate regulation.
Earth's internal structure consists of four main layers: the crust (outermost layer), the mantle (beneath the crust), the outer core (liquid iron and nickel), and the inner core (solid iron and nickel). These layers have distinct properties and play roles in geological and geophysical processes.
The Earth's core consists of two layers: the outer core, which is a fluid layer composed primarily of liquid iron and nickel, and the inner core, which is a solid sphere of iron and nickel. The movement of the liquid outer core generates Earth's magnetic field.
Approximately 71% of Earth's surface is covered by water, with the majority residing in the oceans. The remaining 29% consists of landmasses including continents and islands. Water plays a crucial role in Earth's climate, weather patterns, and supporting life.
Earth has seven continents: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. These continents vary greatly in size, climate, and biodiversity. They are separated by oceans and seas and have distinct geological and cultural features.
Earth is divided into 24 time zones, each generally spanning 15 degrees of longitude. This division reflects the Earth's rotation, with each time zone representing a one-hour offset from the adjacent zones. Time zones help standardize time across different regions and facilitate global coordination.
Earth's magnetic field is generated by the movement of molten iron and nickel in the outer core, a process known as the geodynamo. This movement creates electric currents, which produce a magnetic field extending into space. The field protects Earth from solar wind and cosmic radiation.
The greenhouse effect is a natural process where greenhouse gases, such as carbon dioxide (CO2), methane (CH4), and water vapor, trap heat in Earth's atmosphere. This trapped heat maintains Earth's temperature, making it suitable for life. However, excessive greenhouse gas emissions are enhancing this effect, contributing to global warming.
Climate change refers to long-term alterations in temperature, precipitation, and other climate patterns. It is driven largely by human activities, such as burning fossil fuels and deforestation, leading to increased greenhouse gas concentrations. Impacts include rising global temperatures, melting ice caps, more frequent extreme weather events, and disruptions to ecosystems and biodiversity.
Earth's rotation on its axis causes the cycle of day and night. As Earth rotates approximately once every 24 hours, different parts of the planet face the Sun, experiencing daylight, while the opposite side experiences night. This rotation creates the daily cycle of sunrise and sunset.
Human activity significantly impacts Earth through various means, including deforestation, pollution, and industrial emissions. These activities contribute to climate change, habitat destruction, and loss of biodiversity. Urbanization and resource exploitation alter natural landscapes, leading to long-term environmental challenges and affecting global ecosystems.
Famous Quotes on the Earth
“The Earth does not belong to us: we belong to the Earth.” – Marlee Matlin
“Look deep into nature, and then you will understand everything better.” – Albert Einstein
“The Earth is what we all have in common.” – Wendell Berry
“We won’t have a society if we destroy the environment.” – Margaret Mead
“The Earth is what we have in common.” – Wendell Berry
“We won’t have a society if we destroy the environment.” – Margaret Mead
“The Earth does not belong to us: we belong to the Earth.” – Marlee Matlin
“The Earth is what we all have in common.” – Wendell Berry
“To see the Earth as it truly is, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the Earth together, brothers on that bright loveliness in the eternal cold—brothers who know now they are truly brothers.” – Archibald MacLeish
“We do not inherit the Earth from our ancestors; we borrow it from our children.” – Native American Proverb
“The good man is the friend of all living things.” – Mahatma Gandhi
“Nature is painting for us, day after day, pictures of infinite beauty.” – John Ruskin
“The Earth will not continue to offer its harvest unless we take care of it.” – Ancient Proverb
“Earth provides enough to satisfy every man’s needs, but not every man’s greed.” – Mahatma Gandhi
“The Earth is what we all have in common.” – Wendell Berry
Web references on Earth
- NASA (National Aeronautics and Space Administration): NASA’s website provides a wealth of information on Earth, space exploration, and related topics. Their Earth Science Division offers valuable data and research findings: NASA Earth Science
- NOAA (National Oceanic and Atmospheric Administration): NOAA is a trusted source for climate, weather, and environmental information. Their website contains a vast amount of data and resources related to Earth’s atmosphere and oceans: NOAA
- USGS (United States Geological Survey): The USGS offers geological data, maps, and research related to Earth’s geology, natural resources, and hazards: USGS
- ISRO Earth Observation Data (Bhuvan): Bhuvan is an online geoportal developed by ISRO that offers a wealth of Earth observation data and satellite imagery. It provides access to various Earth-related datasets and tools for visualization: Bhuvan – ISRO
- ISRO Earth Sciences Program: ISRO’s Earth Sciences Program focuses on studying various Earth-related phenomena. Their website offers information on research, projects, and Earth science data: ISRO Earth Sciences
- ESA (European Space Agency): ESA provides insights into Earth observation and space exploration missions with a focus on Europe’s perspective: ESA
- UCAR (University Corporation for Atmospheric Research): UCAR’s website includes educational resources and information on atmospheric and climate science: UCAR
- Smithsonian National Museum of Natural History: The Smithsonian offers educational content related to Earth’s history, geology, and ecosystems: Smithsonian Earth
- Geological Society of America: This professional organization provides geological research, publications, and educational resources: Geological Society of America
- WMO (World Meteorological Organization): The WMO’s website offers insights into meteorology, climate, and weather-related topics on a global scale: WMO
- UNEP (United Nations Environment Programme): UNEP provides information on environmental issues, sustainability, and Earth’s ecosystems: UNEP
- The Earth Observatory: This NASA-funded website offers articles, images, and data on Earth science, climate, and environmental topics: The Earth Observatory
Interesting facts on Earth
Blue Planet: Earth is often referred to as the “Blue Planet” because approximately 71% of its surface is covered in water, primarily in the form of oceans.
Unique Magnetic Field: Earth has a magnetic field created by its molten iron core. This magnetic field acts like a protective shield, deflecting harmful solar radiation and cosmic rays.
Diverse Ecosystems: Earth is home to an incredibly diverse range of ecosystems, from lush rainforests and vast deserts to icy polar regions and deep-sea hydrothermal vents.
Tallest Mountain and Deepest Ocean: Mount Everest, the highest point on Earth, stands at 29,032 feet (8,849 meters) above sea level. In contrast, the Mariana Trench in the Pacific Ocean is the deepest point on Earth, plunging down to about 36,070 feet (10,994 meters) below sea level.
Unique Moon: Earth’s moon, often simply called “the Moon,” is unusually large compared to Earth’s size. It is also responsible for stabilizing Earth’s axial tilt, which gives us relatively stable seasons.
Volcanic Activity: There are more than 1,500 potentially active volcanoes on Earth. Many volcanic eruptions contribute to the formation of new landmasses.
Diverse Climate: Earth boasts a wide range of climates, from the extreme cold of Antarctica to the scorching heat of deserts. These climate variations are influenced by factors such as latitude, elevation, and proximity to bodies of water.
Lifesaving Ozone Layer: The ozone layer in Earth’s stratosphere protects life on the planet by absorbing most of the Sun’s harmful ultraviolet (UV) radiation. The discovery of the ozone hole over Antarctica in the 1980s led to international efforts to reduce ozone-depleting chemicals.
Rings of Space Debris: Earth has several rings of space debris, including defunct satellites, spent rocket stages, and other fragments. These rings, also known as “space junk,” orbit our planet and pose a challenge for space exploration.
Unique Fossils: The Burgess Shale in Canada is renowned for its exceptional preservation of fossils from the Cambrian period, providing valuable insights into early life on Earth.
Ever-Changing Landscape: Earth’s surface is constantly changing due to geological processes like plate tectonics, erosion, and volcanic activity. Landforms evolve over millions of years.
Water’s Unique Properties: Water, a fundamental molecule for life on Earth, has several unique properties, including its ability to expand when it freezes (ice floats), making it less dense than liquid water.
Precious Goldilocks Zone: Earth occupies the “Goldilocks zone” or habitable zone in our solar system, where conditions are just right for liquid water to exist, a key ingredient for life as we know it.
Cultural Diversity: Earth is inhabited by a rich tapestry of cultures, languages, and traditions, making it a melting pot of human diversity.
Home to Life: Earth is the only known planet to support a wide array of life forms, from microscopic organisms to complex ecosystems.
Academic references in terms of books and published articles on Earth
Books:
- “The Blue Planet: An Introduction to Earth System Science” by Brian J. Skinner and Barbara W. Murck – This comprehensive book provides an in-depth exploration of Earth’s systems, including geology, atmosphere, hydrosphere, and biosphere.
- “Earth Science” by Edward J. Tarbuck, Frederick K. Lutgens, and Dennis G. Tasa – A widely used textbook that covers Earth science topics, including geology, meteorology, and oceanography.
- “Physical Geography: The Global Environment” by H.J. de Blij, Peter O. Muller, and Jan Nijman – This book looks into physical geography, including Earth’s landforms, climate, and ecosystems.
- “Earth System Science: A Very Short Introduction” by Tim Lenton – A concise introduction to Earth system science, exploring how Earth’s various components interact and influence the planet’s overall behavior.
- “Climate Change: The Science of Global Warming and Our Energy Future” by Jason Smerdon – This book provides an overview of climate science, including the causes and consequences of climate change.
Published Research Articles:
- “The Anthropocene: A New Epoch of Geological Time?” by Paul J. Crutzen and Eugene F. Stoermer, published in the journal “Global Change Newsletter.” This seminal article discusses the concept of the Anthropocene, a proposed new geological epoch characterized by human influence on Earth’s systems.
- “The Carbon Cycle and Climate Change” by Charles D. Keeling, published in “Earth System Science in the Anthropocene.” This research article discusses the Keeling Curve, which shows the increase in atmospheric carbon dioxide concentrations over time.
- “Observations: Surface and Atmospheric Climate Change” by Thomas R. Karl et al., published in the journal “Bulletin of the American Meteorological Society.” This article presents observations of climate change, including rising temperatures and changing precipitation patterns.
- “The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2008” by Jeremy Jackson et al., published in the journal “Status of Coral Reefs of the World.” This research article provides an assessment of the health and status of coral reef ecosystems in the United States and the Pacific.
- “The Global Water Cycle: Climate and Human Impacts” by Ellen W. Woolfenden and Mary C. Barth, published in the journal “Water Resources Research.” This article discusses the global water cycle, its role in climate, and the impact of human activities on water resources.