This is Earth Science Week, in the US at least. It's an idea that deserves, through globalisation or international intellectual contagion, to be celebrated worldwide. Sponsored by the American Geological Institute, and supported by a consortium of earth science organisations, it is also underpinned by the Earth Science Literacy Initiative funded by the National Science Foundation:
The Earth Science Literacy Initiative (ESLI).... has gathered and codified the underlying understandings of Earth sciences into a succinct document that will have broad-reaching applications in both public and private arenas. It establishes the “Big Ideas” and supporting concepts that all Americans should know about Earth sciences. The resulting Earth Science Literacy framework will also become part of the foundation, along with similar documents from the Oceans, Atmospheres and Climate communities, of a larger geoscience Earth Systems Literacy effort.
The primary outcome of the Earth Science Literacy Initiative is a community-based document that clearly and succinctly states the underlying principles and ideas of Earth science across a wide variety of research fields that are funded through the NSF-EAR program, including Geobiology and Low-Temperature Geochemistry, Geomorphology and Land-Use Dynamics, Geophysics, Hydrologic Sciences, Petrology and Geochemistry, Sedimentary Geology and Paleobiology, and Tectonics.
It goes (I hope) without saying that the fundamentals of Earth Science Literacy are principles that all human inhabitants of our planet should be familiar with - a utopian aspiration perhaps, but it would arguably make our planet a better place. The fundamentals have been distilled into nine "Big Ideas," each with its own set of supporting concepts, and the summary and guide can be downloaded from the website as a pdf. And it's a compelling document; an Earth Science literate person is defined as someone who
• understands the fundamental concepts of Earth’s many systems
• knows how to find and assess scientifically credible information about Earth
• communicates about Earth science in a meaningful way
• is able to make informed and responsible decisions regarding Earth and its resources
As I read through the nine Big Ideas (and being the arenophile that I am), I was struck by the way in which the stories that sand has to tell can form a theme, a narrative thread that weaves through each of the ideas, illustrating and developing. So below are the nine Big Ideas, each one illustrated by sand, together with links to posts on Through the Sandglass that are but a minor sampling of those stories. This is, on the one hand, something of an indulgence, a sort of retrospective of this blog so far, but, on the other hand, I would like to think that it might be an inspiration, a different, and entertaining, route to Earth Science Literacy.
1. Earth scientists use repeatable observations and testable ideas to understand our planet. And a large variety of scientific principles are harnessed to reveal the complexities of the earth system.
Whether it's in the field or the laboratory, as providing vital testaments to the Earth's history or revelations on surface processes and the bizarre behaviours of granular materials, sand and sandstones provide crucial evidence and insights. Sedimentary structures allow reconstruction of past environments and events, a typical integration of fundamental physics, engineering, mathematics, and fieldwork led to our first understanding of how deserts work, and analysis, through granular physics, of the underlying laws of natural systems sheds light on a wide range of phenomena.
2. Earth is 4.6 billion years old. And throughout its history enormous changes have occurred through gradual and catastrophic processes.
The age of our planet is determined from meteorites and lunar materials, but the oldest bits and pieces formed on the earth itself are sand grains - zircons from Australia dating back more than 4.2 billion years. And zircon grains have many tales to tell of our planet's tumultuous history of change. And then the entire sedimentary record of the earth's history, incomplete and variable as it is, represents the fundamental ledgers of the saga.
3. Earth is a complex system of interacting rock, water, air, and life.
Whether inorganic in origin, formed from the disintegration of rocks under the assault of atmospheric weathering, or biogenic, formed from shell and other organic debris, sand tells the stories of chemical and hydrologic cycles, energy and material transfer, and mass balances of natural materials. The size of sand grains influences the appearance of the entire planet.
4. Earth is continuously changing.
Sand, by its very nature, is perhaps the most dynamic of natural materials, and geological change on a human timescale is daily illustrated by shape-shifting bodies of sand on our coasts, in our oceans, and in our rivers and deserts.
5. Earth is the water planet.
And sand is a ubiquitous participant in the great game that water plays in earth processes. Go to the beach and watch the game in action in miniature, or wonder at the huge scale of marine sand transport, the complexity of coastal processes, or the changing dynamics of rivers (with or without human interference).
6. Life evolves on a dynamic earth and continuously modifies earth.
Evolution is a fact. Sand preserves the evidence and can drive ongoing evolution today. Microorganisms are the most widespread, abundant, and diverse group of organisms on the planet, and many of them spend their lives in the company of sand grains. Our beaches host biodiversity possibly greater than that of the rain forest; bacteria turn sand into sandstone, and countless critters build their homes from sand. And then there are the provocative ideas on the interactions between organic and inorganic evolution.
7. Humans depend on earth for resources.
And sand represents a huge resource in countless ways. Electronics, concrete, and precious minerals are but a few examples of sand as a resource - and think how much of our water and hydrocarbons reside in the pore spaces between the grains of sand and sandstone reservoirs.
8. Natural hazards pose risks to humans.
The residents of New Orleans or Samoa whose houses were filled with sand following hurricane Katrina and the recent tsunamis are only too aware of this. The good folk of the Red River Valley, desperately filling sandbags during the floods of earlier this year know all about natural hazards. Desert towns around the world face the threat of moving sand every day. But careful earth science investigation of past catastrophes - for example, tsunami forensics - can help us understand these risks and prepare for future events.
9. Humans significantly alter the earth.
Boy, do we ever. Earth Science Week this year is dedicated to climate change, but there are endless other examples of our footprint. We dramatically change sediment budgets, altering our coasts on a daily basis; we completely disrupt the natural dynamics of rivers and their sediment transport role. And we do these things often for the most trivial and short-term reasons.