Coralline Algae Aids in Climate Reconstruction

Scientists are studying coralline algae at the Labrador Sea in the North Atlantic Ocean. These algae (Clathromorphum compactum) can be used to study the progression of the ice cover in the Arctic sea over the last 150 years. The purpose of the study is to reconstruct the past climates on Earth (Climate Reconstruction)

Climate reconstruction aims to reconstruct a consistent record of the Earth's climate dating back to thousands of years. By understanding the long term history of Earth's climate, scientists can explain and project the planet's current and future climate trends. Scientists usually drill for sediments which can reveal the past state of the Earth's climate.

The new method of using studying algal deposits on the ocean floor is similar to the practice of using tree rings to track the passing of the time. With algae, these "rings" can be as small as 30 microns. Scientists study the magnesium levels in these layers which is dependent on the amount of sunlight and water temperature.

Past climate data only goes back 150 years but with the new method of using coralline algae, this record can go back to the life span of the algae which is more than a thousand years.

Evidence Show Decline of Caribbean Coral Reefs Due To Low Carbonate Production

Research evidence show that coral reefs in the Caribbean have started to decline.

Corals are marine animals living in a cluster of identical polyps. Basically, a polyp is an individual organism within a coral community. Most corals consist of many small polyps living together in a large group or a colony. These polyps, which are cylindrical and elongated, are inter-connected to each other directly or indirectly.

Corals can be found in different shapes and sizes. A striking feature of these corals are the vibrant colors they come in. The colors are provided by a small algae called zooxanthellae. The algae uses sunlight to perform photosynthesis, providing the coral with necessary oxygen.

The relationship between the algae and corals are mutually beneficial. The coral provides the algae with shelter and nutrients needed for photosynthesis. In return, the algae produce oxygen and help the coral to remove wastes. Most importantly, zooxanthellae supply the coral with glucose, glycerol, and amino acids, which are the products of photosynthesis. The coral uses these products to make proteins, fats, and carbohydrates, and produce calcium carbonate

Research Point To Microbe As Cause For Ocean's Methane Levels

Methane is a simple chemical molecule and is a principal component of natural gas. The chemical formula for methane is CH₄. It is colorless and odorless.

Methane is created by bacteria that feeds on organic material. During the process, some methane can get trapped in the ground while some rises up to the atmosphere where it breaks down to (CO₂) and water (H₂O).

When methane is burned in the presence of oxygen (O₂, carbon dioxide (CO₂) and water (H₂O) is produced. The principal use of methane is as a fuel.

Methane is classified as a greenhouse gas. It has a global warming potential (GWP) of 30. This means that for each kilogram (k) of methane emitted to the atmosphere has the equivalent forcing effect on the Earth's climate of 30 times that of carbon dioxide over a 100 year period. Methane has a short lifespan and usually breaks down within 10 years of its release to the atmosphere.

According to an April 2012 NASA report, cracks in Arctic sea ice are leaking alarming levels of methane.

Study identifies prime source of ocean methane

Up to 4 percent of the methane on Earth comes from the ocean's oxygen-rich waters, but scientists have been unable to identify the source of this potent greenhouse gas. Now researchers report that they have found the culprit: a bit of "weird chemistry" practiced by the most abundant microbes on the planet.

The findings appear in the journal Science.

The researchers who made the discovery did not set out to explain ocean geochemistry. They were searching for new antibiotics. Their research, funded by the National Institutes of Health, explores an unusual class of potential antibiotic agents, called phosphonates, already in use in agriculture and medicine.

Many microbes produce phosphonates to thwart their competitors. Phosphonates mimic molecules the microbes use, but tend to be more resistant to enzymatic breakdown. The secret of their success is the durability of their carbon-phosphorus bond.

"We're looking at all kinds of antibiotics that have this carbon-phosphorus bond," said University of Illinois microbiology and Institute for Genomic Biology (IGB) professor William Metcalf, who led the study with chemistry and IGB professor Wilfred van der Donk. "So we found genes in a microbe that we thought would make an antibiotic. They didn't. They made something different altogether."

The microbe was Nitrosopumilus maritimus, one of the most abundant organisms on the planet and a resident of the oxygen-rich regions of the open ocean. When scanning microbial genomes for promising leads, Benjamin Griffin, a postdoctoral researcher in Metcalf's lab, noticed that N. maritimus had a gene for an enzyme that resembled other enzymes involved in phosphonate biosynthesis. He saw that the microbe also contained genes to make a molecule, called HEP, which is an intermediate in phosphonate biosynthesis.