Into the Danger Zone The green zone represents safe boundaries of each of nine environmental hazards for planetary health. The red areas show our current status. Stockholm Resilience Centre

Publishing in the journal Nature, a group of 29 scientists have established a comparative scale for rating the immediate threat posed by nine environmental hazards--everything from climate change to ocean acidification. And while our warming climate gets most of the attention, more immediate problems may be brewing in our intensifying lack of biodiversity and out-of-whack nitrogen cycle.

Of the nine ongoing hazards (climate change, ocean acidification, ozone depletion, the nitrogen and phosphorus cycles, freshwater use, land use, biodiversity loss, aerosols in the atmosphere, and chemical pollution) the group pegged nitrogen runoff as our second-worst problem, and biodiversity as the first. There's not enough data, the researchers say, to accurately plot chemical pollution or aerosol contamination on their scale, but as you can see, we're already in what they've defined as the "danger zone" for three conditions--climate change being the third, in order from worst to still-pretty-terrible.

As for nitrogen, it's an essential nutrient for plants, so we've been pulling nitrogen gas out of the atmosphere to make nitrogen fertilizer. Then that extra fertilizer ends up getting washed into lakes and streams by the rain. Algae in the water think this is delicious and they multiply like crazy, clouding the water and choking out other life. Like fish. And at the end of the day, our actions with nitrogen also end up putting nitrous oxide (a greenhouse gas) into the atmosphere.

But the biggest problem right now is biodiversity. The current rate of extinction is about 100 to 1,000 times greater than what's been healthy throughout the planet's history. The paper points to our land-hogging ways, upsetting the balance of nature to cause more forest fires and other natural disasters, and producing invasive species as the main culprits. The biodiversity problem is expected to get even worse in the future, as rising temperatures threaten animals across the globe.

To learn more and read the scientific article, check out the Stolkholm Resilience Centre, which helped put together the paper.

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12 Comments

if humanity can't change its practices yesterday (i guess its too late for that), or have a mass exodus into the rest of the solar system, the biosphere will fall apart and humanity, for the most part, will be wiped out. Hopefully enough diversity will be left over for earths biosphere to start over after how ever much time it takes the ocean's pH levels to balance, our pollutants to decompose into safe/safer substituents, or what ever else we've done to mess things up to return to normal...if at all. even after humanity disappears, and our buildings crumble away (life after people anyone?) the chemical signatures of our activities may never be erased.

most humans live, natural selection has mostly stopped. There is no need to be intelligent to survive these last centuries. sure a lot of us smart, but most of us don't really care about the planet or are to lazy to change our own habits.

its like we can see the train thats coming to run us over, but instead of running off the tracks we are crawling. we're going to get squashed.

A few questions: What scale are they using? What did they define as the "danger zone?" How did they quantify their results? What data did they use?

As far as I can tell from reading the related link, they arbitrarily chose numbers that they felt represented a danger zone. It's pretty obvious they started wtih a strong bias toward the problems they consider catastrophic.

Disregarding the appearance of legitimacy that comes from publishing in Nature, it's apparent that the assumptions they based their studies on are flawed. For example, they say "Observations of...melting of almost all mountain glaciers around the world." It's hard to believe that a sampling of only 40 to 300 glaciers--depending on how long a timeline the sample is from (2 years to 10 years)--could accurately represent the roughly 160,000 glaciers around the world which differ dramatically by climate, humidity, soot accumulation, precipitation and local environmental changes. They did give a brief nod to the fact that many of the small number of glaciers being studied actually grew. Did you notice it? It's the part where they said: "...almost all mountain glaciers..." Almost.

If the study scientists can tell us that their glacier data accurately represents what's going on around the world with a straight face, it's hard to accept the other assumptions they made. I guess when they say they're using a "novel framework" what they mean is they've conjured up a new way to cherry-pick data and produce erroneous and alarming results.

By the way, I'm dying to know why they couldn't quantify the results of chemical pollution. That has been one of the most studied and quantified areas of environmental science in the last 30 years. Maybe it's because in many countries chemical pollution has been reduced significantly, as we've seen here in the U.S. I dunno. Just thinking out loud.

enuf biodeversity?!? Listen, pal. Using non-scientific terms, you CANNOT save the planet, you CAN only save yourself.

The planet will do just fine once it rids itself of the virus that has ruined it for every other species. That's US. When we're wiped off the face of the Earth, or reduced to an endangered species, it will go about diversifying its bio like it has for millennia. The earth is just fine.

We, as a species, on the other hand, have got to reduce our numbers, reduce our footprint, reduce our trash, reduce our impact, reduce, Reduce, REDUCE, REDUCE!!! Or, go away. Our choice.

People who try and claim intelligence yet cannot use proper grammar or punctuation are really annoying.

People who truly think that humans are the problem and look forward to the day that Earth rids itself of this “virus” should just kill themselves to help everyone else.

Don't forget, the Earth created us in its attempt to biodiversify.

I love when people talk about humanity as if they aren't human. Please tell me that when you look onto the mirror the first thing you say to yourself is "I am a virus to this planet and I must be stopped,".

My point is that I don't think you say this, and I get the feeling that you don't even think this. If you did you wouldn't be waxing intellectually on a random website, you'd be out trying to fix the problem.

Please, everybody, if you are not actively taking action to correct the perceived problem, don't preach about the problem.

Spreading awareness as a first step is a lazy man's excuse for taking action. Do something.

Here's an interesting question that's rarely asked during those huge global warming crisis conferences: Does anyone know what the primary, global warming-causing greenhouse gas is?

Oh, I do.

WATER VAPOR

The amount of carbon dioxide, methane, nitrous oxide and synthetic gases in our little greenhouse is negligible compared to the amount of WATER VAPOR. So I think, you know, we should stop boiling our water in pots, and we should stop watering our plants, BECAUSE WE'RE CAUSING GLOBAL WARMING!!!

These idiots who keep bleating on about water vapour being a problem are annoying. Water is cycled. What goes up comes back down. It's all part of the Earth's natural mechanism for heat regulation.
Granted, when it's warmer you will get more water vapour. But that's the symptom, not the cause.

Evaporated water can absorb and re-emit infrared radiation in the Earth's atmosphere and directly cause an increase in the temperature. I think that more than qualifies as a cause rather than just a symptom of global warming. You are right about one thing: more heat means more water evaporation, which will result in more heat, thus mo problems.

You should know what you're talking about before you call people idiots. It will make you look less pathetic, but only a little less.

Water evaporates from an increase in temperature. And the more evaporated water you have, the more water vapor you have. And the more water vapor you have, the HIGHER CHANCE OF PRECIPITATION.

It's not 'water evaporates and stays in the atmosphere'. It cycles.

elegantmanhood has a terrible name and looks pretty pathetic, missing the point of NOM's post.

Good point Llama.

... and a good name.

These water-vapour doomsayer morons must bew a tad worried living on a planet >70% covered in water.

ok. so i guess the sarcasm of my first comment pretty much eluded everyone, so i'll blame myself for that one. But, llama, wow - my popsci username? really? hey man, whatever gets you through the day and makes you feel a little bit better about yourseslf i'm going to have to support, even if it is at my expense. (including you nom)

Have a good day.



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