Ice Core Data’S Pivotal Role In Determining Planet’S Suitability To Host Life
As the possibility of life beyond Earth continues to be a highly explored topic, understanding how human beings’ planet formed is increasingly crucial. With detailed knowledge of the exact temperature and atmosphere that existed when Earth evolved, researchers can then use this data to look for similarities in other probable, intelligence-bearing planets. Recovering ice cores from areas like Antarctica and studying them in labs to reveal information about previous Earth conditions is currently one tactic being used by scientists. Findings have proven influential in constructing a complete picture of the early planet, especially in regards to climate. As this takes place, new discoveries of planets and stars throughout the Milky Way galaxy constantly arise. In utilizing ice core results, researchers can apply such conclusions toward their assessments of new potential habitable zones of life and forge conclusions on extraterrestrial intelligence.
To understand the past, scientists have been working for years to cut ice cores and gain insights into Earth’s environment. The contents of these pieces are extremely significant for researchers: “airborne relics of Earth's earlier climate… [are trapped in glacial ice] and tell a story about how [the] planet's climate and atmosphere have changed over thousands of years” (Dusto). Remnants of this type can include ash, dust, pollen, sea salt, and most importantly, air bubbles. These bubbles hold prior concentrations of gases like carbon dioxide and methane from centuries ago, and samples enable researchers to directly measure gas levels (BAS). Also, carbon dioxide is pivotal in understanding the concepts of climate change and the greenhouse effect, so obtaining such information is very enlightening for investigators.
Formation of ice sheets began thousands of years ago. As each year’s snowfall compacted down onto one another at the North and South poles, glacial ice several miles deep formed (Stoller-Conrad). Data in these cores reach back 123,000 years in Greenland, and 800,000 years in Antarctica, and imprinted records such as temperature are visible on water molecules (BAS). When researchers drill, “they collect ice cores in many locations around Earth to study regional climate variability and compare and differentiate that variability from global climate signals” (Stoller-Conrad). By tracking these indicators and comparing figures across centuries, researchers construct an accurate picture of different facets of Earth’s atmospheric past. Obtaining precise information from cores is another notable function of this technique, as scientists can validate that their findings are concrete.
Ice core data serves an even greater purpose in terms of predicting civilization’s future, and the tactics used in revealing such information enable experts to form these conclusions. The results scientists gather influence areas across the globe, especially coastal ones. Over time, the Earth has gone through several cycles of heating and cooling, and cores can verify whether “Antarctica's western ice sheet melted fully the last time Earth's climate warmed to the temperatures the planet is predicted to reach in the next two centuries” (Dusto). Since these patterns have persisted throughout Earth’s history, such melting may repeat itself, “which would raise sea levels significantly enough to threaten many seaside cities” (Dusto). Analyzing ice evidence is a meticulous task, but the results are evidently very telling.
The process of understanding the components of an individual ice core take place in the lab after field workers have safely recovered them from areas like Antarctica and Greenland. Retrieval can last several months, depending on factors like weather and the amount of drilling taking place (Dusto). When scientists get to the test center, they crush the ice into smaller pieces and examine them under a vacuum hood to discover the different types of gas bubbles present. Instruments including mass spectrometers and gas chromatographs are also used to locate sulfates, radioactive particles, and aerosols (Dusto). Post analysis of these individual signals of the past, researchers can make comparisons amongst their collection of cores based on what they are investigating. For example, traces of different isotopes of oxygen— oxygen-16 and oxygen-18— enable the study of global temperature variations.
Maintaining cores long enough— from first withdrawal to storage at the lab facility— is essential for preservation of climate data. After logging in the ice cores they obtained, researchers place them into cylindrical tubes packaged in waterproof cases (Stoller-Conrad). Often, cores travel across countries, so having proper flight settings are necessary to keep them from deteriorating. As Erich Osterberg, an assistant professor in the Department of Earth Science at Dartmouth College studying ice cores, puts it, "there's no insurance dollar you can put on it: they're priceless” (Dusto). The U.S. National Ice Core Laboratory in Colorado stores the United States’ entire collection, making assessing samples across centuries convenient and organized for those involved in research (Stoller-Conrad). Studies are pivotal in evaluating the conduciveness of an extrasolar planet for ongoing, sustained life based on what is learned from ice cores about Earth’s history.
Several facets of planetary atmospheric past can be revealed through recovered data. Greenhouse gas concentrations are one of the major topics investigated via the use of ice cores and have indicated various trends in temperature throughout Earth’s lifetime. Cores from Antarctica below areas with high snowfall rates have fully formed air bubbles which [image: ]can be directly compared to readings from stations in the same area on the ground. Ice cores like the Law Dome ice core are dependable mechanisms for inferring clues about carbon dioxide levels (BAS). This is significant since carbon dioxide is instrumental for scientists attempting to understand climate change: as a gas that absorbs heat, it captures immitted infrared radiation and magnifies the natural greenhouse effect on Earth (Lindsey). Additionally, visual paleoclimate graphs can be formulated from these numbers.
Carbon dioxide levels on Earth are currently reaching record levels, as NASA reported 409 ppm (parts per million) as their newest reading as of their August 2018 survey at Mauna Loa Observatory in Hawaii. Emissions of CO₂ have increased due to the abundant usage of fossil fuels like coal to serve the world’s energy demands, and deforestation (Lindsey). Based on recovered data, CO₂ is about 40 percent more highly concentrated in the atmosphere than it was pre-industrial revolution (BAS). Although fluctuations existed hundreds of thousands of years before present day, a tremendous spike occurred extremely recently in Earth’s life. This jump surpasses previous highs of 300 ppm by over 100 points, and human activity is primarily responsible.
Ice core data mirrors the increases in carbon dioxide levels over the majority of Earth’s past. The rate of these growths is especially noteworthy: “the fastest large natural increase measured in older ice cores is around 20ppmv in 1,000 years. CO2 concentration increased by the same amount, 20ppmv, in the last 10 years” (BAS). This has serious implications for future civilizations and confirms the significance of extrapolating records from ice cores. Large changes in global CO2 can then be analyzed by scientists to verify the positive relationship between temperature and this greenhouse gas. Prior lab results represent this connection, as there are “no examples in the ice core record of a major increase in CO₂ that was not accompanied by an increase in temperature” (BAS). As such, when Earth underwent its last warming period, the pair rose together, which served as another mark substantiating the role of CO2 in climate change. This can be seen through data ranging back 21,000 years ago.
Despite the relatively consistent variations in CO2 occurring throughout the roughly 800,000 years leading up present, there are prior instances in which temperature, another variable related to climate change, increased remarkably drastically. In Greenland’s last glacial period, the oxygen isotope ratio, a temperature proxy, specified a roughly 11°C jump in temperature over just 40 years (BAS). Ice core data illustrates [image: ]temperature variances over a 25,000-year period and highlights the quick, 11°C change in temperature within an extremely short time span. Learning about these types of shifts from ice cores further stresses the importance of this practice: such data proves “the climate is capable of extraordinary changes within a human lifetime” (BAS). Knowledge of Earth’s climate oscillations can usefully be applied toward America’s surveying of possible intelligence-supporting planets in future years.
Presently, increases in the melting rates of Greenland’s ice sheets as a result of temperature inclines revealed by ice cores pose a tremendous threat to mankind. Findings documented in the Geophysical Research Letters resulted from a joint collaboration of Boise State University, the University of Alaska at Fairbanks and the University of Maine, and demonstrate that within the last 450 years, Greenland’s melt rates have never been as high as they are right now (Mooney). As temperatures continue to rise on Earth, amplified by record high carbon dioxide and methane levels, this trend will only worsen. So much so that “if global energy demand continues to grow and to be met mostly with fossil fuels, atmospheric carbon dioxide will likely exceed 900 ppm by the end of this century” (Lindsey). By examining the dark areas of snow and light areas of ice within the 100-foot-cores drilled in West Greenland, researchers validated conclusions of the effects of temperature rise. Samples were compared to previous cores in the 1990’s and to ones dating as far back as 1547, indicating rapid changes in ice sheet melting (Mooney).
With this, scientists are able to better understand the implications posed to societies across the world. Just as oxygen isotope data from the British Antarctic Survey supports a prior instance of extreme temperature increase in Greenland, this study from the Geophysical Research Letters further expresses the climate variability cultivated, in part, by changes in temperature and greenhouse gas concentration. The study on melting rates is especially troublesome “because the snow that has fallen on [Greenland] over millennia — now compacted into ice — could raise sea levels by 20 feet if it completely melted” (Mooney). Even having small percentages of these ice sheets melting can be hazardous for civilizations, especially coastal ones, and precipitate much larger storms globally. Much of this currently held knowledge would not be accessible to society without recent technological advancements and the comprehension of ice cores.
In May 2018, an excursion took place to recover ice cores aiding the documentation of the Southern Hemisphere’s climate patterns. At the Mount South Brown location in East Antarctica, researchers led by Dr. Tessa Vance, from the Antarctic Climate and Ecosystems Cooperative Research Centre, drilled for cores over 300 kilometers below ground (Street). The ten-week project was a joint effort between the Australian Antarctic Division, University of Copenhagen, Australian National University and University of Alberta. Vance stated that one of the purposes of this trip was to monitor fluctuations in ice cores over time to unveil evidence about Australian rainfall patterns (“Deep Field Ice Core”). Such data can illustrate the continent’s susceptibility to droughts and floods as well, enabling city planners to have a well-informed grasp on the region’s history and better prepare for future weather conditions (Street).
After completing their drilling, the ice was sent to the Antarctic Climate and Ecosystems Cooperative Research Centre to be analyzed. Another component being tested in these ice samples was sea salt: these particles indicate factors including the prior wind circulations of the Pacific Ocean and the drought variability of Australia (Street). Other information collected from this new set of ice cores will only improve existing knowledge of East Antarctica’s climate history. Dr. Mark Curran, Australian Antarctic Division glaciologist, emphasized that these cores add a wealth of information about a newly investigated area, effectively filling in the holes of pre-existing conclusions (“Deep Field Ice Core”).
On numerous facets, ice core knowledge has proven monumental to the world of science. As the world develops at a high pace, our knowledge of Earth’s prior conditions can help individuals make more informed decisions about aspects of their lives such as energy usage and urban planning. Human beings directing attention towards renewable, environmentally friendly energy outlets like solar and wind power will not only save the planet’s atmosphere, but they make logical sense: sunlight energy gives off hundreds of times more energy than the globe uses on an annual basis. Recognizing the benefits of alternative energy comes about from detailed studies of ice cores— markers from hundreds of thousands of years ago displaying the large leap in Co₂ concentrations worldwide encourage modern societies to turn away from sources emitting high levels of greenhouse gases (Dusto). Without ice cores, data pointing toward renewables would be less supported by science, and people would have a much less robust awareness of their impact on the planet.
In terms of urban planning, oxygen-16 and oxygen-18 isotopes functions as temperature proxies to relay global warming rates. These temperature rises of only a few degrees throughout the last hundred years are extremely significant, because “seventeen of the 18 warmest years in the 136-year record all have occurred since 2001, with the exception of 1998” (“Global Surface Temperature”). The diagram on the right highlights the roughly 1°C jump in temperature since 1880, which is to be highly regarded, even though it is just a degree. With warming of about a few degrees, loss of sea ice results in the loss of polar animals’ habitats, and mankind becomes more likely to experience sea level rise in the future. As this is happening, effects can be devastating to human beings and cause trouble for cities lying near the water (Mooney). Thus, studying ice cores with the purpose of influencing the way populations construct their cities with regards to global climate is another key function of exploration.
As society searches for the possibility of life beyond this planet, taking all of the findings currently being made about Earth’s climate and atmosphere into account is crucial toward guiding the pursuits of researchers. Understanding the pre-existing conditions that enabled the planet to develop the way it did— and host a population of over seven billion people— indicate what scientists should be looking for in potentially habitable areas throughout the Milky Way galaxy. The precise details obtained from ice cores ranging back years into the past act as more than just a gauge for comprehending where Earth is headed throughout its lifetime in terms of the greenhouse effect and temperature inclines. Proxies studied in ice cores can be valuably applied toward tests defining the suitability and likelihood of life-bearing planets. Without this practice of ice core retrieval, efforts for finding life in the galaxy would be much less directed and accurate, which is why this method is arguably one of the most fundamental components to successfully detecting extraterrestrial intelligence.
