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Top Ten Environmental Concerns of the 21st Century

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Kerry loves to write about business, finances, and making the most of your world.

The Biggest Environmental Problems

What are the top ten environmental problems facing the world today? A recent scientific paper published in Nature attempted to answer this question... with a twist.

The authors of Planetary Boundaries: Exploring the Safe Operating Space for Humanity attempted to identify the most serious environmental threats the human race currently faces. They also set out to determine the potential "tipping points" beyond which the pleasant Holocene era would disappear and the Earth's natural resources would be seriously depleted.

The Ten Most Serious Environmental Problems

  1. Climate change
  2. Loss of biodiversity
  3. Phosphorus cycle
  4. Nitrogen cycle
  5. The water cycle
  6. Ocean acidification
  7. Chemical pollution
  8. Atmospheric aerosol pollution
  9. Land-use changes
  10. The stratospheric ozone layer
The Holocene Era mapped out.

The Holocene Era mapped out.

What Is the Holocene Era?

The Earth has spent roughly the last 12,000 years in a period of unusual climate stability known as the Holocene era. To put this era in perspective, all major human civilizations have existed since the beginning of the Holocene. In fact, humans have only practiced agriculture for roughly the last 10,000 years. This all-important development, which allowed civilizations from the ancient Sumerians to our own to thrive, was made possible by the stable climate of the Holocene.

Unfortunately, this stable, pleasant period is currently coming to an end. There is strong reason to believe that this is not the result of a change in the natural cycles of the Earth but rather that the change is caused by human activity.

1. Climate Change

The most controversial of the planetary tipping points named by the Planetary Boundaries Report is climate change. Climatology is a complex science, and some believe that the changes of the past few decades are nothing but natural variations. However, the overwhelming majority of climate scientists believe that human activities are currently affecting the climate. Like many other scientists, the Planetary Boundaries team believes the tipping point has already been passed.

In order to maintain the stable Holocene climate humans have enjoyed for the last 12,000 years of our existence, a majority of scientists now believe that atmospheric carbon dioxide levels must remain below 350 parts per million (ppm). (This level is still 75 ppm higher than pre-industrial levels of 275 ppm.) Beyond 350 ppm, we begin to risk catastrophic and effectively irreversible changes, such as the disappearance of the Greenland ice sheet, which is already melting at a rate of 48 cubic miles (200 cubic kilometers) per year. Currently, the atmospheric carbon dioxide level is 390 ppm and climbing by nearly 2 ppm every year.

Reducing atmospheric carbon levels is likely to be one of the most difficult challenges in a century of difficult challenges. It will require a worldwide improvement in energy efficiency and conservation, a massive push to more carbon-neutral forms of energy generation, and a revolution in land-use practices.

The good news is that climate change is intimately connected with each of the other environmental problems outlined in this article. By solving climate change, we can help solve other environmental problems, and by solving other environmental problems, we can likewise help reduce the problem of climate change. Pick an issue, study it, and create the change you want to see in the world.

The Science of Climate Change

Artist's rendering of ocean life in the late Permian, shortly before the Permian-Triassic extinction event.

Artist's rendering of ocean life in the late Permian, shortly before the Permian-Triassic extinction event.

Artist's rendering of ocean life in the early Triassic, shortly after the Permian-Triassic extinction event.

Artist's rendering of ocean life in the early Triassic, shortly after the Permian-Triassic extinction event.

2. Loss of Biodiversity

Of the three "tipping points" the authors of Planetary Boundaries believe the human race has already passed, the loss of biodiversity is the most dramatic. The Earth is currently in the midst of the greatest mass extinction since the death of the dinosaurs 65 million years ago. As many as half of all plant and animal species that exist today could be extinct by 2100, a rate that is an estimated 1000 times the natural rate of 0.1-1.0 species per million species per year.

This catastrophic loss of biodiversity is already likely to affect the development of life on earth for millions of years to come. Following the largest mass extinction in Earth's history - the Permian-Triassic extinction event that occurred about 251 million years ago - it took 50 million years for land-dwelling species to regain their previous diversity and more than 100 million years for ocean biodiversity to recover.

The cause or causes of the Permian-Triassic extinction are still unknown, but the cause of the current mass extinction sadly is not. The majority of modern extinctions are directly or indirectly caused by human activity. Habitat destruction, overhunting/overharvesting, competition from invasive alien species, and climate change are a few of the most common causes of extinction.

In addition to an almost unimaginably impoverished world, mass extinction also threatens to lead to the collapse, domino-style, of entire ecosystems, ecosystems that the human race depends on for its own survival. So-called "ecosystem services" are believed to save human societies trillions of dollars every year by performing functions such as the following:

  • Purification of air and water
  • Crop pollination
  • Production of seafood, game, and other wild foods
  • Pest control
  • Waste decomposition
  • Soil creation
  • Drought and flood mitigation

Healthy ecosystems perform ecosystem services more effectively than stressed or destroyed ecosystems.

3/4. The Phosphorus and Nitrogen Cycles

Although the effect of human activities on the carbon cycle is better known, the effect of human activities on the nitrogen cycle has been even more dramatic.

The human race's use (and abuse) of the nitrogen cycle has been one of the most beneficial for our own species for many years. Every year, humans convert 120 million tons of nitrogen from the atmosphere into reactive forms such as nitrates, mainly in the production of nitrogen-based fertilizer for crops. The widespread introduction of nitrogen fertilizers to the world's farmers was one of the driving forces of the remarkable Green Revolution of the 20th century, which increased crop yields in most regions of the globe by up to ten times.

However, human activities now remove more nitrogen from the atmosphere than all natural processes combined, and much of this nitrogen ends up as a pollutant. A particularly serious problem is nitrate pollution from agricultural runoff in ground and surface water supplies, which can not only poison humans and other living creatures drinking polluted waters, it can also significantly change freshwater and marine ecosystems. The Gulf of Mexico "Dead Zone" is caused by nitrate and phosphate pollution, primarily from agricultural runoff in the American Midwest. The fertilizers cause massive algae blooms, which consume all the oxygen in the water, leaving it too low in oxygen for anything to survive. The size of the Dead Zone varies from year to year, but it generally covers about 6000-7000 square miles and has seriously impacted fisheries in the area, as well as the health of the local ecosystem. Other Dead Zones exist in the Baltic Sea, the Black Sea, Chesapeake Bay, and some parts of the Pacific Ocean, as well as freshwater lakes and rivers around the world.

Phosphate pollution contributes to the problem as well, though to a far lesser degree. Unlike nitrogen, which is extracted from the air, phosphorus is mined.

The authors of the Planetary Boundaries report believe that the nitrogen cycle has already long passed its tipping point, and the human race should strive to reduce its consumption of atmospheric nitrogen to 35 million tons per year to return to sustainable levels.

One way to reduce nitrogen consumption is to increase the use of nitrogen-fixing cover crops such as clovers and other legumes and compost and animal manures as fertilizer.

5. The Water Cycle

Many experts believe that water depletion will be one of the most pressing issues of the 21st century. Currently, 1/3 of humans have inadequate access to clean, fresh water. By 2025, the number is expected to reach one-half to two-thirds of the human population, thanks to a combination of many factors, including water pollution, climate change, and water depletion from unsustainable water uses.

Inadequate water resources have led to violent conflict throughout human history, but never on the scale that is likely to affect the 21st century. In addition to human suffering and armed conflicts, unsustainable water use also affects the environment as a whole. For example, irrigation of crops can lead to salinization of soil, ultimately leading to desertification and loss of habitat and biodiversity. Another concern is rising ocean levels. Recent studies have linked groundwater depletion around the world to rising sea levels. Rising sea levels already threaten many island nations and low-lying coastal regions.

6. Ocean Acidification

Ocean acidification is a lesser-known side effect of excessive CO2 production. About 1/4 of the CO2 produced by human activities every year is dissolved in the oceans, where it reacts to form various compounds, including carbonic acid, that increase the acidity of seawater. Over the last 250 years, the surface acidity of the ocean has increased by an estimated 30%. The acidity is expected to increase by 150% by 2100.

The effects of this change are still poorly understood. However, what is known is that increased acidity decreases the amount of carbonate in seawater, an important component of shells for many shellfish, plankton, and skeletons for coral. The effect of more acidic seawater is similar to that of the disease osteoporosis on human bones - the shells and skeletons gradually become softer and weaker. Eventually, the shells and skeletons dissolve completely. Since shellfish and plankton provide food for many other creatures and coral reefs offer one of the richest and most biodiverse ocean habitats, this could result in a disastrous domino effect for ocean ecosystems, leading to the collapse of many fisheries and eventual extinction of thousands of species.

7. Chemical Pollution

Pollution of air, water, and soil by long-lasting chemical compounds is another tipping point that is hard to quantify. Many of the chemicals in question simply have not been around long enough for their long-term effects to be clear. These include many compounds suspected of being endocrine disruptors, chemicals that interfere with the natural balance of hormones in the body.

Some of these endocrine-disrupting chemicals are blamed for a sudden rise in hermaphroditism among aquatic creatures such as fish and frogs. Others are believed to contribute to the rise in breast cancer, prostate cancer, and other hormone-related cancers in humans.

Other pollutants, such as some heavy metals, are already known to be both harmful and persistent.

8. Atmospheric Aerosol Pollution

Atmospheric aerosols can be either natural or manufactured. Unlike greenhouse gases, most aerosols have a net cooling effect on the climate because they reflect sunlight back into space instead of allowing it to warm the Earth. The famous Year Without a Summer in 1816 resulted from large amounts of natural aerosols being thrown into the atmosphere by the 1815 eruption of Mount Tambora.

Unfortunately, excessive aerosols are nevertheless undesirable because of their damaging effects on human and animal health, among other things. Smog and other forms of air pollution contribute to chronic respiratory illnesses and even deaths for millions of people every year. In fact, the World Health Organization estimates that 2.4 million people every year die as a direct result of aerosols and other forms of air pollution. This problem is most severe in industrialized areas and areas that use "slash-and-burn" agriculture methods or wood fires for cooking.

This chart depicts loss of virgin forest in the US between 1620 and the present, and demonstrates the scale of some of the land use changes humans have perpetrated.

This chart depicts loss of virgin forest in the US between 1620 and the present, and demonstrates the scale of some of the land use changes humans have perpetrated.

9. Land-Use Changes

The authors of Planetary Boundaries chose Land Use Changes as one of their top environmental concerns, which I felt was a slightly redundant choice because changes in land use, for the most part, have the same negative effects as several of their other choices.

For example, loss of wildlife habitat leads to loss of biodiversity. Depending on what the habitat is replaced with, the change can also lead to air or water pollution from factories and farm fields, depleted groundwater reserves due to impervious surfaces such as city roads, and carbon emissions from almost any human activity you could name.

Land Use Changes are also particularly difficult to define as a "tipping point" because their effects vary significantly. In fact, the exact environmental impact of one land-use change is different from the impact of every other land-use change ever made.

I feel a less redundant and easier-to-measure choice might have been soil depletion due to erosion, desertification, and unsound agricultural practices, among other factors.

10. The Stratospheric Ozone Layer

The ozone layer filters out the most harmful wavelengths of UVB ultraviolet radiation from the sun before it reaches the earth's surface. A depleted ozone layer would mean increased rates of skin cancer for humans, as well as damage to plants and ecosystems. Ozone depletion received a lot of attention in the 1970s and '80s when scientists discovered a giant and growing "hole" in the ozone layer above Antarctica.

Fortunately, the scientists convinced the world community to act quickly to limit the production of ozone-depleting substances such as CFCs and halons. The ozone depletion problem today seems to be on the path to a successful resolution. However, due to the long lifetime of ozone-depleting compounds, the Antarctic ozone "hole" is not expected to recover completely until 2050. The overall ozone levels in the atmosphere will recover to pre-1980 levels only about 2060 2075.

The goal for the future will be to maintain the progress we have already made on this issue.


Richard O on September 01, 2019:

What can I say apart from lets all of us globally, hope and pray when it comes to environmental issue we have to face, lets hope we haven't gone over the tipping point. Very interesting article you've published there it gives us a widening area of How can we address this a soon as possible and hope that if we all make change today then maybe just maybe. we'll have a TOMMOROW...???

SARA from Islamabad on May 02, 2019:

Very informative. Thanks for sharing

Ifrah Bashir from Pakistan on May 01, 2019:

A very informative and interesting piece of writing.

Diane Denison from Cincinnati Ohio on May 22, 2018:

A Terrific Article In Which You took Intense Time to Write. Further more you covered every Part Of The Environmental Concerns...

varsha bang on August 03, 2017:

A great article indeed.

Marion Micah Tinio on May 31, 2017:

Reading this in 2017, and I found one missing environmental concern: overpopulation. Population is the root of all environmental problems, and it is the most complicated concern to deal with.

MR. Rahul Raj on June 12, 2016:

now our environment is better now compare to 21th century

i would like to tell to you all plz give me the help by that we clean our environment .

Krzysztof Willman from Parlin, New Jersey on April 08, 2015:

This is quite a read with great detail and information. I've always stressed the importance of climate change and I've been a huge weather and climate hobbyist for years. People are finally getting it that there's a problem going on. Since this article was written, we've had the warmest year on record, record breaking droughts, floods, and massive superstorms and hurricanes plaguing the earth. The levels of carbon dioxide have exceeded 400 ppm, which haven't been seen since humans have been on this Earth.

Also the levels of extinction for various plant and animal life is approaching crisis mode and the year 2015 is already highly likely to surpass 2014 as the warmest year ending the so called hiatus. Excellent read voted up.

Misha on September 14, 2013:

Ha! Enjoy:


Ryan Rafferty on April 04, 2013:

very nice hub. Sad to see that these issues have long been identified and there has been very little progress being made on them. Hopefully more awareness will bring about more change.

Mat on February 16, 2013:

Wow. Impressive Hub i must say. I am all for it.

Romel Tarroza from Philippines on February 15, 2013:

Environmental concerns is a concern of everybody. We must act to preserve our world. This hub is very informative.

Suhail Zubaid aka Clark Kent from Mississauga, ON on February 14, 2013:

Most interesting read ever on environment concerns. I wonder why population explosion didn't appear in the list.

However, I am glad that an area that I tend to cover in my hubs and on Facebook for my followers, that is, biodiversity and wildlife conservation, did make it to the list.

Thank you for sharing a very informative hub.

Angela Kane from Las Vegas, Nevada on February 14, 2013:

Great hub and information. My biggest concerns are chemicals and water.

Malek Zarzour from Turkey, Istanbul on February 14, 2013:

very useful and interesting hub. Voted up.

JITENDRA from INDIA on February 14, 2013:

very interesting hub .........and the information is very supportive

Chen on February 13, 2013:

I had heard about some of these, but not all of them. What a great resource you've compiled here... so informative, and it';s so important to get the word out. Great hub, vU & Useful!

Susette Horspool from Pasadena CA on January 31, 2013:

OK now I can see it. Evaporation of irrigation spray and runoff of excess water into the storm drains is causing as much sea level rise as melting glaciers. That's amazing . . . and an important addition to the book I'm writing. Good article, thanks!

kerryg (author) from USA on January 31, 2013:

watergeek, there are quite a few groundwater reserves that are far from any ocean. Scientists have found that groundwater depletion is adding about 0.8 millimeters per year to sea level rise.

Soil salinization due to irrigation has been a problem for thousands of years, long before chemical fertilizers, etc. came into play. Salts from the irrigation water are left behind in the soil after the water evaporates and over time these accumulate. There are ways of managing the problem, including flushing out the salts with more water, but it's still a well documented problem.

Susette Horspool from Pasadena CA on January 13, 2013:

Great article, Kerry, as usual. However I do have a possible correction or two. You state that groundwater depletion leads to rising sea levels. I disagree with that. Groundwater depletion actually leads to absorption of sea water, as desiccated ground around the edge of the ocean sucks it up like a sponge. It's the melting of landbound glaciers (Iceland, Greenland, etc) that adds volume to the ocean.

Secondly, it's not the irrigation of crops, per se, that leads to soil salinization. It's the use of crop-related chemicals and the breakup of mycelium underground that does it. Mycelium (mushrooms are their fruit) break down complex compounds like fertilizers, so other microbes can use them as food, which makes nutrients available for plants. When the mycelium nets are broken up by tilling, they can't do their job. Fertilizers, herbicides, and pesticides collect in the soil and get washed down by whatever water is applied - irrigation, rain, floods. Water actually cleans salts from the ground as it sinks down into the aquifer.

Amit Mittal from Patiala, India on July 01, 2012:

Hope the world will work together to solve these problems

mimie on May 22, 2012:

very interesting

ancestralstory from Brisbane, Queensland, Australia on April 29, 2012:

Interesting hub. Good to see some media used in the article - always helps with understanding. Thanks.

hi friends on April 26, 2012:


Michael Toole from Ozark, Alabama on April 25, 2012:

Very, planned, motivated, and unique Hub, +1 on this Hub, keep up the good work! :)

laringo from From Berkeley, California. on April 24, 2012:

As I watched Frozen Planet last Sunday this topic about our oceans it just goes to show how we should never take our planet for granted. I really enjoyed this Hub and learned a lot from it.

Sarahhh666 from near Philly on April 20, 2012:

I had to write a college paper on this subject recently. I wish I would have read this first! Lol.

Tiffany Delite from Wichita, KS on April 18, 2012:

this is a great hub...our family recycles, and i try to be overall conscience of the environment, but typically when i think of pollution, i tend to think of air pollution and/or just the large amount of garbage humans create. i never really stopped to think about all of the other elements that are polluted when we live carelessly. voted up and interesting...thanks!

Laura Tykarski from Pittsburgh PA on April 17, 2012:

I vote this up and awesome. Although fairly new to the hub community I have read quite a few hubs that have made a lasting impact on how I view things i.e. the environment,social issues and political ideologies. I will be looking for the documentary you used via You-Tube as this subject really interests me and has for some time. Living in PA which is largely "pro-fracking" I have wondered often how it will effect our soil (already know how it is going to effect our long-term water supply which even a laymen can surmise is going to effect our soil as well. Ty for a well documented and research hub I will be using it to start looking deeper into this issue as well.

hi friend from India on April 17, 2012:


panpa on April 12, 2012:

Worrying about the earth's future. Great hub

shepheka on April 12, 2012:

Over the last 250 years, surface acidity of the ocean has increased by an estimated 30%. The acidity is expected to increase by 150% by 2100....

30% of the entire ocean, covering 75% of our planet?

This number is quite enormous, I am not really sure I can believe it.

Ruth McCollum from Lake Oswego, Oregon on April 12, 2012:

Wow I got alot out of this article.Thankyou .I live in Oregon ,so we are big on trees and we have a great recycle programs. It's plain common sense to put things where they can be reused ,than fill our landfills with garbage it'll take years to start to become part of the earth. Oregon pioneered the recycle program.

That being said I think this was a great article,people need to read!

hi friend from India on April 12, 2012:

more informative. good luck

amithak50 from India on April 06, 2012:

Chemical pollution,ocean solidification all are great concerns ..We have to do something to remove it otherwise we have to pay off in future

Chris Achilleos on April 04, 2012:

Thank you for sharing this very informative hub. The more knowledge people get of this matter the better chances we have to save the earth. Voted up and interesting!

hvacunits from Longview, TeXas on April 03, 2012:

Simply an amazing Hub. Thanks so much for all your wonderful work. "Awesome." A big vote here for your hub! Just had to share it on Twitter and Facebook with my followers!

iguidenetwork from Austin, TX on April 03, 2012:

Nice - very interesting!

networmed from SPL on April 03, 2012:

You're absolutely correct on that @Mlssilva. A simple recycling which we can start at home can be of help if we all do it, or at least the majority of the people will do it.

Mlssilva from Figueira da Foz on April 03, 2012:

Well done! A very informative and educational hub. It is unfortunate that despite the man being aware of how much it hurts the planet Earth, the measures taken are insufficient. I am concerned about the future of next generations. How will be the planet Earth in the future if we continue to neglect it at this rate? We must do something now and quickly.

Vegas Elias from Mumbai on April 03, 2012:

This is a very informative article. I feel consumerism is the main cause of most of the ills man is faced with. We consume more leading to more production which in turn leads to pollution and the other undesirable effects.

Anyway a very eye opening article and deserves praise.

Guyene Jackson from USA on March 30, 2012:

It is a good think that we have this kind of Ocean Acidification post really Good.

Dr Pandula from Norway on March 30, 2012:

Thank you for a great hub with lots of information. Nicely presented! Voted up.

alzheimersfacts from Santa Fe, NM on March 22, 2012:

Great hub! Very interesting.

LauraGT from MA on March 22, 2012:

Thanks for the incredibly informative hub on a sometimes dry and hard to plow through topic. Great job on this important topic.

maxgraham441 from NYC on March 21, 2012:

Great Hub! Surprised to see Russia in the "No-Stress" category.

taw2012 from India on March 21, 2012:

useful information. Nice hub about the hot topic.

ackman1465 from Cape Coral, Florida on March 21, 2012:

I believe that it's likely that we (humans) are mostly at risk for totally depleting the fossil fuel supplies before we face any of the other disasters enumerated in Kerry's hub.

My take on it is found in this submittal, which I made relative to gasoline prices.....


ackman1465posted 8 days ago

The entire fossil-fuel picture is really pretty amusing.... Consider this riddle:

If you find yourself low of fuel while driving on an expressway.... you might exhaust your supply of gas at any moment ... what is the smartest way to proceed? .... to go FASTER, to get to a gas-station SOONER? ... or, drive still slower, in the belief that your car will burn LESS GAS at that slower pace? ... BUT, you'll have to be patient, as you'll drive slower, longer...

The answer is the latter, of course... and there's plenty of quantifiable details to explain it....

BUT, back to amusing.... I see us HUMANS as the one(s) with the low fuel supply (the Earth's supply of fossil fuels is, after all, finite)... and many people are proposing that we race like crazy to find those last supplies - wherever they are - and burn THEM.... overlooking that, ultimately, our "tank" will go empty!!!!

We will be wise to morph/adjust our means of making electricity (the "real" power, after all) to some other source besides fossil fuels. We can do so in a measured, deliberate manner, over time.... OR, we can do so in haste, maybe even in chaos, under the impending threat of our running out of fossil fuels altogether....

Fuel prices (the original subject of this thread) are strictly subject to market considerations.... and "the market" these days, is much more of "the World" competing for the available crude than was the case 20, 50 or 75 years ago.... The price at the pump reflects THAT.... and EVERY PROSPECTIVE PRESIDENTIAL CANDIDATE WHO CLAIMS THAT HE HAS THE "SECRET PLAN" TO REDUCE GASOLINE PRICES AT THE PUMP is deluding himself and hoping, as well, to delude you!!!!!

mikeydcarroll67 on March 21, 2012:

Interesting hub!

Ruth McCollum from Lake Oswego, Oregon on March 21, 2012:

This Hub was so informative. You gave me some really great insight.great hub voted up!

TotalHealth from Hermosa Beach, CA on March 21, 2012:

Nice hub! It's crazy to think about how our actions impact the environment. Sammythrone pointed another important fact about water supply. I'm curious, do people realize the rate at which the world population of humans is expanding? As we know, this planet has a limited supply of natural resources. I wonder what life will be like in 20 years. ~ Great job!

Leena Martha from USA on March 20, 2012:

Very informative but at the same time very, very hard to read. Its so sad what is happening to the Earth. You presented what needs to be brought to everyone's attention... Thanks for sharing great hub.

networmed from SPL on March 20, 2012:

Hi kerryg... Thank you for enumerating all these problems we are facing currently. This will serve as reminder for all of us that we should do something about it.

sammythrone from North America/South America/Europe/Asia on March 20, 2012:


I think, we humans are really responsible for all the environmental concerns. Like what you have mentioned in #5, water is going to be a big concern. And I'm not surprise. What do you think is our most pressing environment issue?

Guyene Jackson from USA on March 16, 2012:


We have follow the every people than after take care in forest.

Actually article is every important?

chrae from Melbourne, Australia on March 16, 2012:

Fantastic Hub, all very relevant issues that will continue to effect to people on earth into the future. In my opinion more needs to be done about these issues and prevent global disasters. I wrote a hub specifically about no. 10 here:

Eliminate Cancer from Massachusetts on March 15, 2012:

Excellent - what an IMPORTANT hub!!

Your loss of biodiversity is one I am particularly concerned with, the effects of Genetic Engineering is complicating this. GMOs are becoming ubiquitous, and are cross pollinating with other plants - the political and legal issues are crazy. It's affecting our health, it's affecting our environment, and it's irreversible.

While other countries are banning this, sadly, we are supporting it. We need more active citizens and articles like yours to spread the word, and save our planet and ourselves!!

louromano on March 12, 2012:

We live environment. We have to decrease environmental pollution.Need is the mother of invention, I have faith in humans, we aren't perfect but the sh*t hits the fan we usually come through.:) But before that can happen we need articles like these to spread more awareness.

skinsman82000 from Maryland on March 06, 2012:

No one can deny that global warming is taking place in the world. But the sources exactly is an interesting discussion topic. I think it's most likely a mixture of natural climate change that is always happening and humans hurrying that change along with pollution. Great Hub. Voted Up.

Mahaveer Sanglikar from Pune, India on February 15, 2012:

@ kerryg

This is a very informative and interesting Hub, not only for common readers but also for students of this subject. Thank you for sharing it. Voted up and shared.

mrshadyside1 from Georgia on February 09, 2012:

Great hub! As far as Global Warming is concerned if anyone would actually think about the planet and civilization it's not hard to see that Global Warming has to be occurring.Every person on the planet produces a body temp of 98.5 degrees add that to all the light bulbs producing heat plus in-home-heating and industrial heat production,it has to be warmer now than anytime in man's history. That's not even accounting for all of the asphalt paving laid out everywhere,which if you have ever walked out on the driveway barefoot in summer,you will understand is trapping a huge amount of heat and holding it long after sundown. Asphaltic Shingle Roofing also traps a lot of heat. Without the other causes we would be experiencing increased temperatures. It blows my mind that anyone could not see this to be true.Anyway,that was a very good hub,thanks for the information.

bmukherjii on February 07, 2012:

I am really shocked to see this hub. at the same time I am really worried about the fact that you mentioned in your hub regarding acidification of ocean waters that will gone up to 150% in next 100 years..I don't know whether our earth is heading towards another dissaster

ftclick on February 07, 2012:

I don't come back to many hubs but this is one I will stay on top of. I remember we used to drink from the hose in the late 70s as kids in our front yard. I see "no water stress" levels in the Brazil but nobody there drinks water from their own faucet either but they will boil it. So, that is a bit misleading

kerryg (author) from USA on February 06, 2012:

Helpingyoufindit, thanks for the reminder. Though I am a liberal, I consider concern for our environment to be something far beyond politics. Politics (and religion, too) become completely irrelevant if we no longer have a livable planet, therefore it's in the best interest of everyone - liberal and conservative, religious and non-religious - to promote environmental conservation.

I definitely encourage everyone who reads this hub to read widely on environmental issues and make up your own mind about who is telling the truth. I recommend Skeptical Science as the best starting point. It is pro-AGW and includes detailed refutations of pretty much every anti-AGW argument ever made, but the comments section frequently includes posts by AGW deniers and skeptics that bring up other interesting points. At the very least, those readers inclined to disagree with AGW may return with more novel arguments than "it's the sun" and "it's a liberal conspiracy!"

Helpingyoufindit on February 06, 2012:

Kerryg you have a great post don't let this Gusser Guy turn it into a political or religious argument. Gusser must I remind you of 2 Timothy 2:23-24.

Please let people discuss things without changing it into an argument over religion or politics. If you want to discuss those things then find a hub that talks about those things or write your own.

I think allot of us including me have found kerryg's Hub very interesting. I have a brain and can look at the information presented to me and find out for myself what I believe to be true.

kerryg (author) from USA on February 06, 2012:

And conservatives want to bring on the Apocalypse so Jesus will show up and Rapture them out of this world they've ruined. :P

Save the world or destroy it - I know which I'd rather face my Maker having attempted.

Gusser on February 05, 2012:

Ah yes I forgot. Liberals need not believe in a savior. They believe they are the savior. Thousands of little messiahs. Like I said : Your fairytale, you tell it anyway you want.,

kerryg (author) from USA on February 05, 2012:

Reality has a well-known liberal bias. :D

Ironically, it's climate deniers who are more likely to end up causing climate-related loss of freedoms, by delaying sensible gradual action to the point where only urgent, severe action will have any hope of saving our skins.

We need to peak carbon emissions by 2015 to have a hope of keeping warming below 2 degrees C. If we delay even until 2020, we'd have to go down by 10% a year, globally. The total collapse of the USSR reduced its national emissions by only 5%, so I'm sure you can imagine how much fun a 10% global drop would be. :P

Gusser on February 05, 2012:

You certainly believe in the full line of leftist causes. If only you could get laws passed controlling what the deniers are allowed to do. THAT is the real reason behind the Left's agenda. Control. After all only the left has learned people, the rest are to stupid to think for themselves. It's your hub, you can tell your fairytale anyway you wish.

kerryg (author) from USA on February 05, 2012:

I'm not sure why, since it hasn't been definitively confirmed yet. Even if it is, that hardly debunks the scientific method itself. Real scientists admit their mistakes. Climatologists will do the same if it ever becomes necessary. As it stands currently, however, climate skeptics and deniers have poured millions into funding research attempting to debunk anthropogenic global warming without the slightest success. It is certainly possible that it may be debunked in the future, but meanwhile, given that it predicts civilization-ending catastrophe if we don't take action, I feel that this is a clear case where the benefits outweigh the risks.

Even if anthropogenic climate change is ultimately debunked, fossil fuels are a finite resource that should be conserved for indispensable uses, not wasted frivolously. Extracting and burning them is also a major contributor to air, water, and soil pollution worldwide, which kills millions of humans and untold billions of plants and animals every year by exacerbating respiratory problems and causing cancer, birth defects, and other problems via exposure to toxic by-products. Reducing deforestation, unnecessary tillage, and meat consumption also have benefits to both human and environmental health that go far beyond their effects on climate.

Gusser on February 05, 2012:

Still enjoying science's red face over the speed of light being broken. Einstein's THEORY was peer reviewed, past rigorous testing, was the best explaination available, had observational evidence to back it up, Science at its finest. YET COMPLETELY FALSE My sunscreen theory is just as accurate.

kerryg (author) from USA on February 05, 2012:

It hasn't survived any either. It is therefore a hypothesis and not a theory at all. Enjoy your trip to the moon in search of observational evidence to back it up!

Gusser on February 05, 2012:

Your Science had a theory the the Sun orbited the earth. Or getting closer to your time: that the speed of light couldn't be broken. WRONG AGAIN Theory is not proof of anything. AND don't bring the sun into this just because it is the SOURCE of heat for this planet.... WAIT.... The SUN warms our planet. I have a theory that "The man in the moon could apply sunscreen to himself & reflect the suns rays away from earth thus cooling global Warming". This new "theory" has not failed any rigorous testing, And nobody disputes its facts. SCIENCE at it's finest.

kerryg (author) from USA on February 05, 2012:

Sure. There is always the possibility that the sun will go into some deep solar minimum or something and the whole warming trend will reverse. However, it would have to be a very DEEP solar minimum, since humans emit enough CO2 in just 7 years to completely negate a minimum such as the one that caused Europe's "Little Ice Age" a few centuries ago.

Like many anti-science types, you completely misunderstand the concept of scientific theory. In the scientific world, a theory is something that has survived rigorous testing and is the best available explanation for a given phenomenon that fits all the known facts. Gravity is a theory. So is the heliocentric solar system.

Gusser on February 05, 2012:

"Looks like it MAY happen"--- now there is something to hang your hat on. "Looks like" is not proof---"May happen" is not proof. Let's just change our way of life, without proof. Theory is what the whole Global Climate Warming, Cooling, Change thing is. Theory is NOT proof even in the scientific community. The theory is based on SOME evidence pointing to a future happening. SOME evidence, points to the Messiah's return too. Do you state that as FACT also? Some "believe" in the Messiah's return. (FAITH). Some believe in Warming,Cooling, Change. (FAITH). Perhaps you need to recognize Global Warming, Cooling , Change, as the Liberals Religion.

kerryg (author) from USA on February 05, 2012:

Antarctica is gaining sea ice thanks to changes in ocean circulation from freshwater running off from its melting land ice - hardly evidence against global warming.

For the third time, the science of the 70's was NOT predicting an ice age. The possibility was discussed on account of cooling from aerosols, but rejected on the grounds that the cooling effect of aerosols was more than offset by the warming effect from CO2. Newsweek, which is not and never has been a science journal, noticed the discussion but not the conclusion and ran a sensationalist story, thus ensuring that people like you would spend the next 40 years lying about what the scientists said. Thanks, Newsweek.

"AND if science is " consistently *under* estimating" THAT alone shows science to be in ERROR AGAIN."

Yes, but not the way you want them to be in error! The arctic wasn't supposed to be ice free in summer until 2100. Now it looks like it may happen by 2030. This is not good news for a lot of people. Additionally, you will find that when scientists make mistakes, they admit it and correct them. With all the unexpectedly violent climate-related chaos of the last 5 years, the next IPCC report is likely to be a doozy.

Gusser on February 05, 2012:

Less ARTIC ice----oh crap MORE Anartic ice ---oopsy--The "possibility" of pink unicorns was first suggested in 1897.... Proves nothing. Since the 70's means before 1980... when the science of the day was predicting Ice Age. AND if science is " consistently *under* estimating" THAT alone shows science to be in ERROR AGAIN. Believe what you want, that's called faith, not proof.

kerryg (author) from USA on February 05, 2012:

You think if you just keep repeating the same old lie about the majority of scientists predicting global cooling in the 70's it will magically become true?

The possibility of global warming caused by anthropogenic carbon emissions was first suggested by Arrhenius in 1896. Other scientists started to become concerned about it in the 1950s, and it's been the majority scientific consensus since the 70's.

Al Gore's movies did NOT predict New York would be underwater in 2012. That was The Day After Tomorrow, a sensationalized Hollywood vision of global warming. Real scientists (neither Al Gore nor Hollywood qualifies) have actually consistently *under*estimated the speed and violence of changes caused by global warming. There is currently less Arctic ice, for example, than most 2007 IPCC models predicted we would have by 2050:

Gusser on February 05, 2012:

Peer reviewed eh. That simply means one moron agrees with another moron. Morons would be peers CORRECT? These morons did as stated: 1970's & 1980's cry wolf for COOLING. 1990's & early 2000 WARMING. From then to now CHANGE. As far as Civilization ending catastrophe by 2100: These same Peer reviewed Morons predicted that for to be happening NOW. Remember Al Gores movies? New York should be underwater with the rising sea levels. OOPS Thats right Obama was going to " Lower sea levels". The Polar Bears should be extinct, by now. Just saw 1 3 weeks ago on vacation. The Global Warming-Cooling-Change movement is the only thing moving, MOVING from one lie to the next.

kerryg (author) from USA on February 04, 2012:

Actually, reviews of the peer-reviewed scientific literature of the time reveal that the papers predicting warming greatly outnumbered the papers predicting cooling, but you know the mainstream media - always looking to sell another magazine or newspaper with a sensational headline! Apparently Newsweek thought a new ice age sounded more sensational than a global heat wave, so "scientists predict a new ice age" passed into the mainstream consciousness in the 70's, while hardly anybody outside the scientific community discussed the possibility of global warming until the late 80's, despite the fact that the basic science behind the greenhouse effect had been established for 150 years and scientists had been saying that humans might be influencing it for nearly 100.

"An eco system that has survived billions of years, thru astroids, ice ages, warming etc" certainly can survive little old man. The question is whether "little old man" can survive himself. Unchecked global warming has the potential to be a civilization ending catastrophe, literally by 2100. It's pretty clear from your avatar that you don't have to worry about being alive then, and neither do I, but my children by all rights should be, and you'll pardon me if I prefer to do everything in my power to reduce the chance that they will experience total societal collapse. :P

Gusser on February 04, 2012:

Talk about lost. YOUR kind called for a mini Ice Age in the 70's & 80's Reversed itself in the 90's to call it Global Warming. Then being totally exposed as a hoax, had to change your mantra to Climate CHANGE. Now some of the "learned" are going back to the mini Ice Age again. As far a desert scrubland: The desert of Death Valley has sea life fossels. Things changed long before man got here, they will always change. WOW THATS GLOBAL CLIMATE CHANGE, let's blame man. An eco system that has survived billions of years, thru astroids, ice ages, warming etc can certainly survive little old man. If I could buy "Warmers" for what they know, then resell them for what they think they know, I would have wealth beyond imagination.

kerryg (author) from USA on February 04, 2012:

Okay, now you've flipped your previous logic on its head and are suggesting that because man is responsible for one forest fire, then he must also be responsible for all forest fires ever. This is just as illogical as your previous suggestion.

The end of the last Ice Age came about because of the Milankovitch Cycles, and, by the way, dinosaurs died out about 65 million years previously.

The CO2 produced through exhalation by the entire human race, let alone us climate hawks by ourselves, is pretty negligible, so the extinction of the human race, in whole or in part, wouldn't have much effect on plants if exhaling was our only contribution to atmospheric CO2.

Additionally, "the more CO2, the more plants" is a gross oversimplification. Due to their greater genetic diversity, weeds are much more able to take advantage of higher CO2 levels than crop plants, so even if the overall number and growth rate of plants increases, it's not likely to particularly benefit the human race:

Additionally, even the success rate of weeds will depend on how much the rising CO2 levels affect the temperature. Photosynthesis is a temperature dependent process. It slows down above 90 degrees F, shuts down above 95 degrees, and has stopped entirely by 105 degrees, so regions with significant temperature increases can expect reduced plant growth of all sorts despite the higher CO2 levels. For example, the business as usual carbon emissions scenario predicts that Kansas will see 120 days per year above 90 degrees by the year 2090, more than twice the ~50 it gets today and comparable to the climate of modern Tucson or Las Vegas. I know I can't wait to see one of the breadbaskets of our country reduced to desert scrubland. :P

Gusser on February 03, 2012:

So you blame man, how did the last Ice Age end? Man wasn't here, YET the earth warmed. Perhaps you believe the Dyno's were driving SUV's. CO2 can easily be lowered. All Global Warming Morons can stop exhaling. WAIT that would mean the plant life would die since they breathe CO2 & give off oxygen for the air breathers to use. Wow the more CO2, the more plants. The more plants, the more oxygen for us. Isn't that a great way to help life AND the planet?

kerryg (author) from USA on February 03, 2012:

Gusser, by that logic, humans never start forest fires because forest fires have been started by lightning in the past.

We have known that carbon dioxide is a greenhouse gas since the 19th century.

We know that the amount of carbon dioxide in the atmosphere is currently increasing. We also know that the pattern of warming we are currently observing is consistent with warming caused by an increase in CO2. For example, overnight temperatures are warming faster than daytime temperatures because the extra CO2 traps the heat longer near the surface, whereas if the sun were causing the warming you would expect daytime temperatures to warm faster and the heat to be lost fairly quickly to space once the sun went down.

Finally, we know that humans are the primary cause of the increase in CO2, because carbon emissions from fossil fuel burning have a different carbon isotope ratio than carbon emissions from most natural sources such as volcanoes. Carbon isotopes associated with carbon emissions from fossil fuel burning are increasing in the atmosphere and oceans, while carbon isotopes associated with natural CO2 sources are remaining more or less steady, or even declining.

Therefore, since the increase in CO2 is the primary cause of the current warming and human emissions are the primary cause of the increase in CO2, it is logical to say that humans are the primary cause of the current warming. A recent study pegged our contribution at about 74%.

Gusser on February 03, 2012:

If climate "stability" is unusual as you stated at the beginning of this hub, instability is the norm. Climate Change is instability. If instability was present before MAN, what moron would believe it's mans fault concerning climate instability? Science is supposed to be logical. Your conclusions are anything but.

Helpingyoufindit on February 02, 2012:

Keep up the good work. I look forward to reading more of your posts in the future.

chelseacharleston on February 02, 2012:

Well there's just no such thing as too much of this kind of awareness, great hub!

Jennifer Madison from Lohmar on February 02, 2012:

There is lots of useful information in this hub and it is very comprehensive. I like it a lot. People need to become aware of these issues and act accordingly. Especially schools and universities. Climate change and environmental protection measures need to be integrated into the science curriculums of all schools.

john hayls on February 02, 2012:

This hub has very interesting topics for us. All the topics related our socially environment. Thanks for the shearing information.

christopher9882 from Chicago, IL on February 01, 2012:

Thank you for sharing.....

Very interesting.

Matt Dawes from England on February 01, 2012:

Great hub! Good information and nicely written. Voting up and interesting!

quiet tracer from South-Asia on January 30, 2012:

A great effort to bring such a concerning issue in people's view.

Though, nothing is going to be changed positively in favour of the green environment for at least some long time in future. Behaviour comes from the top to bottom. When the largest economies in the world at present are not going to accept to reduce a bit of the growth rate of their economies, how can you imagine the companies and the businesses at any domestic level in those countries will ever dare reducing their productions and excretions for the sake of protecting environment?

People can raise the volume of their voices to cry that the environment is in danger but it does not seem possible that people can ever make the governments to think green. Its just impossible. Every big giant needs money and money comes faster when they destroy the environment. I think you guys get the point.

Eliminate Cancer from Massachusetts on January 30, 2012:

Not just interesting - critically important!! How do we get the message across to the people who can do something about this??

Bill Holland from Olympia, WA on January 24, 2012:

Fascinating hub; much of this I taught in my science classes but I probably never was this eloquent in my delivery. I hope this is read and read and read again. Keep up the good work!

Magicdust Staff from Sydney, Australia on January 24, 2012:

Excellent hub, so full of info and worrisome on several levels. The water situation is possibly closer than we think.

charles wade from Chicago, Illinois on January 24, 2012:

Don’t worry, the same brilliant minds that created so many of our problems will certainly get us out of them; will they not?

SarahBodo on January 24, 2012:

Useful and informative.Am voting this up and sharing it!

Azure on January 22, 2012:


kxdorey from Beverly Hills, California, USA on January 13, 2012:

Another great one that nobody seems to be talking about is the fact the layer of top soil on our Earth is slowly depleting. Because we don't recycle crops, many plants have less than 10% of the nutrition they did even 50 years ago. It's not popular in the media but it's greatly affecting our ability to fight off all these bugs.

SanXuary on January 12, 2012:

There are some other major tipping factors that work against our current agenda but creates some variables that might keep us from committing suicide. Despite the unquestionable truth that global warming has been influenced by carbon we are headed towards another ice age. According to past geology it is a cycle and should return. The other variable is peak oil, it is already impossible to imagine another 80 years of supplies. Right now the battles for control over the last supplies is a game of winner takes all or last man standing. Even more scary is to imagine a World with no oil and having no plan to replace this energy source. Still I find the argument that ethanol is not a good choice. How can a one for one carbon exchange from plants to carbon be bad compared to no exchange but increased carbon. Still if we do not create a plan based on sustainment we are likely facing a longer list.