Channel Islands National Park
Visiting the Channel Islands off the coast of California is like taking a trip back in time. While breathing in the ocean breezes, observing the relatively untouched flora and fauna, and taking in the scenic coastal views, the island visitor can get a feel for what California was like during the days of the California missions and Mexican ranchos - before modern urbanization and development changed the State's landscape. This is largely due to the preservation efforts and formation of one of the newest national parks. Founded in 1980, the Channel Islands National Park is comprised of five islands located off of Southern California's Santa Barbara and Ventura coastlines.​
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The Channel Islands provides three testimonies to the validity of God's Word, the Bible:
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God sets the boundary for the sea (Jeremiah 5:22; Job 38:8-11) and He lifts up the islands (Isaiah 40:15);
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Exploring Santa Rosa Island
Pier from the boat with Santa Cruz Island visible in the background.
The trip to and from the islands is part of the adventure!
Exploring Santa Rosa Island
Come with us on a virtual trip to the Channel Islands.
Testimony #1: Pathways in the Sea
The ocean currents off the coast of California are a significant part of why there is such a huge difference between Northern and Southern California (and you thought it was due to people and politics!). Coming from the north is the California Current which is a cold current with relatively low salinity and high dissolved oxygen content. Arriving from the west is a warm and quite saline current known as the Central North Pacific Water (think Hawaii). Coming up from Mexico and hugging very close to the shoreline is the warm and shallow California Countercurrent and the deeper California Undercurrent. All of these currents collide and mix south of Point Conception in the Santa Barbara Channel where the Channel Islands are located.
The currents are what makes Southern California beaches so nice, warm, and enjoyable; and what makes Northern California beaches so cold and frigid. These currents also affect weather. Warm water produces and helps carry high energy and heavy rainfall producing storm events (e.g., the Pineapple Express); while the cold water off of the Northern California coast produces heavy fog banks and wind even during the summer months. One could argue somewhat successfully that the currents are the reason why people from Southern California are different from those in Northern California. The beach environment affects beach culture which in turn affects local culture. Hence, shave ice and the smell of coconut sunscreen in SoCal, and coffee and sourdough clam chowder bowls of NorCal.
Color gradient map showing the relative water temperatures due to the mixing of the three currents. Yellow indicates warmer water and dark blue indicates colder water. Greens and light blue are areas of mixing.
While the extent of influence ocean currents have on California culture may be debatable, there is no denying that the various ocean currents entering and mixing in the Channel Islands National Park have given each island its own micro-climate and, thereby, has made each island unique in flora and fauna. This provides a visitor to the Channel Islands with a slightly different experience at each island they visit.​
​Anacapa, the smallest of the Channel Islands, is located farthest to the east of the group of northern islands and is in the warmer water has little fresh water sources and is arid and exposed. Therefore, the vegetation tends to reflect this dry and rugged environment. This is contrasted with Santa Rosa, a large island located approximately 30 miles to the west of Anacapa, which has a more diverse blend of terrestrial vegetation. Because Santa Rosa is surrounded by colder waters from the California Current, it tends to have more fog, which allows other endemic plants such as the Torrey Pine and ferns to thrive on the island.
Plants on Santa Rosa island are more diverse and include some that need a wetter environment that is provided by regulare fog banks.
Classic Title
You have made him (man) to have dominion over the works of Your hands ... the fish of the sea that pass through the paths of the seas. Psalm 8
David, who wrote Psalm 8, most certainly did not spend much time traveling the world's oceans and probably did not understand the concept of ocean currents. But moved by the Holy Spirit in this great psalm of praise to God about His creation, David recognizes the role the Creator gave to humans, who were made "a little lower than the angels," to have dominion over animals, birds, and all that pass through "the paths of the seas." While David might not have comprehended the full truth of what he wrote and what eventually would become known as Psalm 8, the Holy Spirt did understand these concepts and would reveal them to another believer approximately 3,000 years later.
Matthew Fontaine Maury (1806 - 1873) was an American naval officer who initially served as a sailor and was later put in charge of the Depot of Charts and Instruments. He told his family that the text of Psalm 8 inspired him to investigate the "paths of the seas." Matthew studied log accounts from numerous ship captains and officers about observations of how adverse winds and drift currents affected their sailing vessels. This lead him to publishing the "Wind and Current Chart of North Atlantic" which helped ship captains to use the ocean currents and winds to their advantage and greatly reduce the time needed for their ocean voyages. This and his subsequent published scientific works have earned him the title Father of Oceanography.
As noted by the psalmist, paths have been found in the sea. Let's take a look at three of them:
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Surface currents
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Thermohaline circulation (aka the Global Conveyor Belt)
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Longshore currents
Paths in the Seas:
Surface Currents:
Surface ocean current patterns. (Credit: David Bice © Penn State University)
Thermohaline Circulation - The Global Conveyor Belt:
The "Global Conveyor Belt" driven by temperature and salinity differences (or thermohaline mechanisms). Source: National Oceanic and Atmospheric Administration (NOAA) National Ocean Service
https://oceanservice.noaa.gov/education/tutorial_currents/05conveyor2.html
Upwelling:
According to NOAA, upwelling is when winds blow parallel to a coastline, it pushes away surface waters and causes the deeper water that is rich in nutrients to rise to the surface. These nutrients (nitrogen and phosphorus which come from dead sea creatures) are vital ingredients for the growth of marine plants, including phytoplankton. These phytoplankton are the foundation of the food web in the ocean. All other animal populations in and associated with the ocean depend upon it or on what consumes it. In fact, it is amazing to think about that the largest animal on earth (the blue whale) feeds upon the smallest animal in the ocean (phytoplankton).
Areas of coastal upwelling, such as those off the coast of California, are some of the most productive ecosystems in the world and support many of the world's most important fisheries. Although coastal upwelling regions account for only one percent of the ocean surface, they contribute roughly half of the world's commercial fish production.
Upwelling does not always occur year round, in the Channel Islands, it primarily occurs in the spring and summer months near the islands of San Miguel and Santa Rosa.
A difference in temperature, pressure, or chemical composition drives many of the processes that we observe in creation whether it involves processes we see in the universe, Earth's atmosphere, or even in our own bodies. It is also a main reason why ocean water is moving from one place to another. When there are differences in water temperature, salinity, and density, it causes water to sink or float - moving it from one place to another. This is referred to as "hermohaline circulation" (thermo meaning heat, and haline meaning salt) which drives ocean water around the world in what is often called the “global conveyor belt.” The conveyor belt begins on the surface of the ocean near the North Pole in the North Atlantic where it is chilled by arctic temperatures. It also gets saltier because when sea ice forms, the salt does not freeze and is left behind in the surrounding water. This makes the water more dense and causes it to sink toward the ocean bottom. Surface water then moves in to replace the sinking water, thus creating a current. The cold deep water moves south past the equator and and continues on between South America and Africa all the way to the Antartica. At this point, the same thing happens that did at the North Pole; the shallow water cools, ice forms, and the more dense surface water once again sinks. As the deep dense water moves along the coast of Anartica, it splits off at two different places and heads north into the Indian Ocean and the Pacific Ocean. These two sections that split off subsequently warm up and become less dense as they travel northward toward the equator. Because they become less dense, they rise to the surface (upwelling) brining along with it bottom nutrients and water rich in carbon dioxide, which are the very things needed to fuel the food chain starting with the bottom of the food chain - phytoplankton. The warm risen water currents then loop back southward and westward to the South Atlantic, eventually returning to the North Atlantic, where the cycle begins again. It is estimated that it takes approximatley 1,000 years for a quantity of water to travel the entire Global Conveyor Belt circuit.
Longshore Currents:
Testimony #3: The Calcium Carbonate Cycle
Acidification of the oceans. Limestone has a pH level of 7.0 and can neutralize the acidity of fish tank water by reacting with the acid in the water. Limestone raises the pH level to a neutral range beneficial to plants, typically between 5.5 and 6.5. The weathering of silicate rocks on land (rocks made of minerals that contain the element silica) is an important part of the carbon cycle. Over long-time scales, significant amounts of carbon dioxide (a greenhouse gas) are removed from the atmosphere when rainwater (H2O) mixes with CO2 to form carbonic acid (H2CO3). This weak acid reacts with rocks, breaking them down, resulting in the transport of carbon via rivers to the ocean, where it ultimately becomes buried in ocean sediments to become limestone rock. In contrast, the weathering of limestone by carbonic acid releases carbon dioxide into the atmosphere, but there is no net removal of CO2 from the atmosphere as happens with the weathering of silicate rocks. Limestone, a sedimentary rock composed primarily of calcium carbonate (CaCO₃), forms via two predominant pathways: biogenic precipitation and abiogenic precipitation. Biogenic precipitation limestone formed primarily from the remains of organisms that secrete calcium carbonate, such as shells, skeletons, and exoskeletons. The final characteristics of biogenic precipitation limestone can vary depending on the types of organisms that contributed to its formation, the size and shape of the organic fragments, and the environmental conditions during its deposition. Some limestones are fine-grained and dense, while others are coarse-grained and porous. The color can also range from white to gray, brown, or even black, depending on the presence of impurities like iron or organic matter. Chemical precipitation representing the primary non-biological process. This mechanism involves the direct conversion of dissolved calcium carbonate (CaCO₃) into solid limestone without the involvement of living organisms. Changes in temperature, pressure, or salinity within a body of water can disrupt the equilibrium of dissolved calcium carbonate. This disruption can lead to its precipitation as solid crystals, which subsequently accumulate on the seabed. The initial step involves the dissolution of minerals containing calcium and carbonate ions in water. This can occur through weathering of rocks on land or from interactions with marine sediments. When the water becomes saturated with dissolved calcium and carbonate ions, it reaches a state of supersaturation. This means the water holds more dissolved ions than it can normally hold under the prevailing conditions. Under the influence of the aforementioned factors, dissolved calcium and carbonate ions combine to form solid CaCO₃ crystals. These crystals precipitate out of solution, accumulating on the seabed or other surfaces. https://www.geologyin.com/2024/02/how-limestone-is-formed-and-where.html
The degree to which calcium carbonate occurs in water at atmospheric pressure depends on the pH and temperature of the water. At pH values of less than about 6, mostly dissolved carbon dioxide and a small amount of carbonic acid exist in water. At pH values of between about 6.5 and 10, bicarbonate is dominant.
Can lakes near volcanoes become acidic enough to be dangerous to people and animals?
Yes. Crater lakes atop volcanoes are typically the most acid, with pH values as low as 0.1 (very strong acid). Normal lake waters, in contrast, have relatively neutral pH values near 7.0. Fresh volcanic ash typically lowers the pH of water. The 1953 eruption of Mount Spurr caused the pH of the public water supply to fall to 4.5; within a few hours, the pH returned to 7.9.
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​Volcanoes emit carbon dioxide in two ways: during eruptions and through underground magma. Carbon dioxide from underground magma is released through vents, porous rocks and soils, and water that feeds volcanic lakes and hot springs. Estimates of global carbon dioxide emissions from volcanoes have to take both erupted and non-erupted sources into account. https://www.climate.gov/news-features/climate-qa/which-emits-more-carbon-dioxide-volcanoes-or-human-activities
https://www.icr.org/article/massive-releases-co2-from-volcanism-rival-humans
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019RG000681
https://www.nature.com/scitable/knowledge/library/ocean-acidification-25822734/
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As is widely known, volcanoes emit large amounts of CO2, the most prevalent greenhouse gas in the Earth's atmosphere. A small number of individuals remain unconvinced that human activities are the major contributors to global warming, and they often direct the blame at the world's volcanoes. The total CO2 emitted from all of earth's volcanoes (approximately 200 million tons per year), however, is less than 1 percent of the CO2 released by human activities. On an annual basis, KÄ«lauea Volcano produces less CO2 than the city of Honolulu.
In contrast, the Earth's oceans are the largest natural reservoir for CO2. Since the beginning of the industrial revolution about 200 years ago, the sea has absorbed about 130 billion tons of carbon, nearly half of the fossil fuel carbon emissions released during this period. The oceans' uptake of excess CO2 generated by humans is starting to take a toll on the chemistry of seawater. When carbon dioxide is absorbed, it reacts with seawater to form carbonic acid. This lowers the pH of the oceans, a phenomenon referred to as ocean acidification.
The pH scale is a measure of acidity and ranges from 1 to 14. A pH of 7 is neutral. Values higher on the scale are more "basic," and those lower, more "acidic." Therefore, a decrease in pH is associated with an increase in acidity. The pH of seawater is currently around 8.05, compared with the value of 8.16 measured about 200 years ago. Like the Richter scale for earthquakes, the pH scale is logarithmic, so a change of one pH unit represents a 10-fold change in acidity. This pH is probably lower than it has been for hundreds of millennia and is changing at a rate 100 times greater than at any other time over these millennia.
The drop in seawater pH wreaks havoc with the chemical equilibrium of calcium carbonate, a mineral that is used by marine organisms, like corals, lobsters, and clams, for building shells and skeletons. As the oceans become more acidic, these organisms will grow more slowly, and corals may be unable to build reefs fast enough to outpace the erosional processes wearing them away. The impacts are likely to propagate throughout the marine food chain, affecting species diversity, commercial fisheries, and tourist economies. There are natural processes that stabilize the pH of the ocean. For instance, the deposit of the basic mineral calcium carbonate onto the sea floor from dead and decaying organisms is balanced by the introduction of fresh calcium and carbonate ions into the ocean from the weathering of rocks on the land. But these processes occur over a time scale of tens of thousands of years, rather than hundreds of years. With the current rate of CO2 increase in the atmosphere, these mechanisms for compensation won't be able to keep up.
Ocean acidification is a straightforward chemical response to increasing atmospheric concentrations of CO2 and is predicted with a high degree of certainty. While the biological consequences of ocean acidification are not yet well understood, initial information indicates that there is cause for concern for the long-term health of our oceans. Of course, other indicators of climate change, such as sea-level rise, are also of concern to us as island residents. https://www.usgs.gov/observatories/hvo/news/volcano-watch-oceans-acid-trip-are-cause-concern
Visitors to San Miguel Island have the opportunity to view the caliche 'forest', where the root system of vegetation that grew on the island several hundred years ago has been turned into caliche casts and caliche root sheaths
Caliche Casts: Caliche is calcium-carbonate cemented soil that is formed in semi-arid climates. Calcium carbonate is derived by the dissolution of shells and shell fragments that have blown across the island from the beaches, especially during the Ice Age when the sea level was much lower and the beaches were more extensive. Rain is a weak acid, formed by reactions between water vapor and carbon dioxide in the atmosphere, and it is this acid that dissolves the shell fragments. San Miguel has a semi-arid climate; so when it rains, the volume of water is too small to carry dissolved materials away from the area, and they remain in the topsoil. This groundwater dissolves the calcium carbonate from shells in the surface layer and re-precipitates it a little lower in the surface profile, where it will act as a cement, binding the soil material into a hard substance that is called 'caliche', or 'calcrete', or 'hardpan'.
On San Miguel Island, the deep root system of trees that grew several hundreds of years ago decomposed, and the molds of the roots filled with the abundant sand that makes up much of the topsoil of the island. The calcium carbonate preferentially cemented the sand-filled molds, possibly because they were more porous and provided an easy pathway for the groundwater.
Caliche Root Sheats: Another form of caliche is where living vegetation, generally a root in the soil, gets a 'sheath' of caliche. The living roots may exude a weak acid, or draw soil moisture towards them by capillary action. In either case, a solution of calcium carbonate from the soil is concentrated around the roots which, when precipitated later, forms a sheath of caliche. When the root dies and rots, the sheath will remain, either as a hollow form, or may be filled with sand, which may become a caliche cast, by the method described above. Many such examples of both hollow forms and filled sheaths can be found on San Miguel Island.
The caliche 'forest' of San Miguel Island was created when strong winds blew away the uncemented sandy soil surrounding the caliche casts and the root sheaths. The visitor to San Miguel Island is treated to this rare glimpse of a landscape turned inside out -- the roots and lower trunks of these ancient plants now stand as 'forests'.
https://www.nps.gov/chis/learn/nature/geologicformations.htm