Still plenty of work to be done for Mother Earth

by Don Gordon, professor emeritus of botany at Minnesota State University, Mankato

Thursday will be the 40th anniversary of Earth Day, and for more than three decades I have been writing annual Earth Day columns to report on the environmental health of the planet. These columns are sobering reminders that we have met the enemy, and he is us.

From the time man first appeared, the planet has been largely viewed as a giant hardware store or as an unlimited free buffet where we could take what we wanted.

Along the way, we didn’t have to worry much about exhausting resources or polluting the planet. When a resource became scarce or an area became polluted, we simply looked elsewhere and moved to another area. That strategy worked pretty well until our population and appetite for resources started to grow exponentially.

In 1800, the planet supported about 1 billion people. Now there are nearly 7 billion, and the United Nations estimates there will be more than 9 billion of us by 2050. Further, there are now more than 1 billion poor people who are chronically undernourished, and the U.N. plan to reduce that number by 2015 will not be met.

Cereal grain growth has declined, and if the temperature increases just 2 degrees C. (3.6 degrees F.), this could lead to an additional 20 to 40 percent decline in cereal yields. To feed an extra 2.5 billion by 2050 will require the developed countries to increase production by 70 percent. Without that increase, there may be more than 2 billion chronically hungry people by 2050.

University of Minnesota environmentalist Jonathan Foley and eight others writing in Scientific American report that, just in the last 50 years, “the global consumption of food and fresh water has more than tripled, and fossil fuel use has risen fourfold.” Man now co-opts between 1 ⁄ 3 and 1 ⁄ 2 of all the photosynthesis on the planet.

The journal Worldwatch recently reported that, in 2006, man consumed $30.5 trillion worth of goods and services, up 28 percent from 10 years ago. We Americans use more than anyone else.

On average, each of us consumes about 194 pounds of resources daily.

If the whole world used resources at this rate, Worldwatch estimates the Earth could sustain only 1.4 billion people or just 1 ⁄ 5 of our current size.

Foley and his group set thresholds for key environmental processes that, if crossed, could threaten the sustainability of Earth.

Their analysis indicated that three thresholds have already been breached.

These include biodiversity loss, nitrogen pollution and climate change.

■ Biodiversity Loss. This rapid rate of consumption is also taking its toll on living organisms. To call attention to this loss, the United Nations has designated 2010 as the International Year of Biodiversity.

Julia Marton-Lefevre writing in a recent issue of the journal Science reports that global loss of biodiversity costs us between $1.35 and $3.1 trillion annually.

Loss of tropical forests is responsible for nearly 20 percent of greenhouse gas emissions; thus, it is a major force in climate change.

Biodiversity loss could cause land and ocean ecosystem failure.

Possible solutions would include slowing land clearing and development and eliminating the idea that nature is free.

They propose establishing a pay system for ecosystem services.

■ Nitrogen pollution. Unless checked, fresh water and ocean hypoxic dead zones will expand.

Possible solutions would include reducing fertilizer use, planting more winter cover crops, planting more perennials, processing animal waste and switching to hybrid vehicles.

■ Climate Change. There has been a lot of misinformation put out on climate change. For example, the claim that the Earth is cooling is bunk, according to NASA’s James Hanson.

Global warming has neither stopped nor slowed in the last decade.

The World Meteorological Organization reported that 2000-2009 was the hottest decade on record. Current carbon dioxide levels of 390 parts per million are the highest in recorded history. Foley’s group thinks 350 ppm was the threshold level.

Unless we mitigate climate change, polar ice and glaciers will melt and regional climates will shift. Possible solutions include switching to low- carbon energy and fuels and put ting a price on carbon emissions.

The environmental solutions proposed by Foley and his group might slow down environmental degradation of the planet, but according to the new book “Eaarth” by Bill McKibben, they might not solve the underlying cause, which is our insatiable quest for economic growth.

According to McKibben, our hope depends on scaling back — on building the kind of societies and economies that are sustainable. As you might guess, the critics have labeled his solutions as unrealistic.