Prior to that, the Permian mass extinction that occurred 250 million years ago, also known as the "Great Dying," was triggered by a massive lava flow in an area of Siberia that led to an increase in global temperatures of 6 degrees Celsius. That, in turn, caused the melting of frozen methane deposits under the seas. Released into the atmosphere, those gases caused temperatures to skyrocket further. All of this occurred over a period of approximately 80,000 years. The change in climate is thought to be the key to what caused the extinction of most species on the planet. In that extinction episode, it is estimated that 95 percent of all species were wiped out.

Today's current scientific and observable evidence strongly suggests we are in the midst of the same process - only this time it is anthropogenic, and happening exponentially faster than even the Permian mass extinction did.

In fact, a recently published study in Science Advances states, unequivocally, that the planet has officially entered its sixth mass extinction event. The study shows that species are already being killed off at rates much faster than they were during the other five extinction events, and warns ominously that humans could very likely be among the first wave of species to go extinct.

So if some feel that McPherson's thinking is extreme, when the myriad scientific reports he cites to back his claims are looked at squarely and the dots are connected, the perceived extremism begins to dissolve into a possible, or even likely, reality.

The idea of possible human extinction, coming not just from McPherson but a growing number of scientists (as well as the aforementioned recently published report in Science), is now beginning to occasionally find its way into mainstream consciousness.

"A Child Born Today May Live to See Humanity's End, Unless ..." reads a recent blog post title from Reuters. It reads:

Humans will be extinct in 100 years because the planet will be uninhabitable, according to Australian microbiologist Frank Fenner, one of the leaders of the effort to eradicate smallpox in the 1970s. He blames overcrowding, denuded resources and climate change. Fenner's prediction is not a sure bet, but he is correct that there is no way emissions reductions will be enough to save us from our trend toward doom. And there doesn't seem to be any big global rush to reduce emissions, anyway.

McPherson, who maintains the blog "Nature Bats Last," told Truthout, "We've never been here as a species and the implications are truly dire and profound for our species and the rest of the living planet."

Truthout first interviewed McPherson in early 2014, at which time he had identified 24 self-reinforcing positive feedback loops triggered by human-caused climate disruption. Today that number has grown to more than 50, and continues to increase.

A self-reinforcing positive feedback loop is akin to a "vicious circle": It accelerates the impacts of anthropogenic climate disruption (ACD). An example would be methane releases in the Arctic. Massive amounts of methane are currently locked in the permafrost, which is now melting rapidly. As the permafrost melts, methane - a greenhouse gas 100 times more potent than carbon dioxide on a short timescale - is released into the atmosphere, warming it further, which in turn causes more permafrost to melt, and so on.

As soon as this summer, we are likely to begin seeing periods of an ice-free Arctic. (Those periods will arrive by the summer of 2016 at the latest, according to a Naval Postgraduate School report.)

Once the summer ice begins melting away completely, even for short periods, methane releases will worsen dramatically.

Is it possible that, on top of the vast quantities of carbon dioxide from fossil fuels that continue to enter the atmosphere in record amounts yearly, an increased release of methane could signal the beginning of the sort of process that led to the Great Dying?

McPherson, like the scientists involved in the recent study that confirms the arrival of the sixth great extinction, fears that the situation is already so serious and so many self-reinforcing feedback loops are already in play that we are well along in the process of causing our own extinction.

Furthermore, McPherson remains convinced that it could happen far more quickly than generally believed possible - in the course of just the next few decades, or even sooner.

Truthout caught up with McPherson in Washington State, where he was recently on a lecture tour, sharing his dire analysis of how far along we already are regarding ACD.

Dahr Jamail: How many positive feedback loops have you identified up until now, and what does this ever-increasing number of them indicate?

Guy McPherson: I can't quite wrap my mind around the ever-increasing number of self-reinforcing feedback loops. A long time ago, when there were about 20 of them, I believed evidence would accumulate in support of existing loops, but we couldn't possibly identify any more. Ditto for when we hit 30. And 40. There are more than 50 now, and the hits keep coming. And the evidence for existing feedback loops continues to grow.

In addition to these positive feedback loops "feeding" within themselves, they also interact among each other. Methane released from the Arctic Ocean is exacerbated and contributes to reduced albedo [reflectivity of solar radiation by the ice] as the Arctic ice declines. Tack on the methane released from permafrost and it's obvious we're facing a shaky future for humanity.

You talk often about how when major industrial economic systems collapse, this will actually cause a temperature spike. Please explain, in layperson's terms, how this occurs.

Industrial activity continually adds reflective particles into earth's atmosphere. Particularly well known are sulfates produced by burning coal ("clean coal" has a lower concentration of sulfates than "dirty coal"). These particles reflect incoming sunlight, thus artificially cooling the planet.

These reflective particles constantly fall out of the atmosphere, but industrial activity continuously adds them, too. When industrial activity ceases, all the particles will fall out within a few days. As a result, earth will lose its "umbrella" and rapid warming of the planet will ensue. According to a 2011 paper by James Hansen and colleagues, the warming will add 1.2 plus or minus 0.2 degrees Celsius. Subsequent research indicates the conservative nature of this paper, suggesting termination of industrial activity will add a minimum of 1.4 degrees Celsius to the global average temperature.

What indicators are you seeing that show the possibility of major economic collapses in the near future?

We cannot sustain the unsustainable forever, and this version of civilization is the least sustainable of them all. It teeters on the brink, and many conservative voices have predicted economic collapse this year or next. According to a June 2012 report by David Korowicz for the Feasta group, a disruption of supply will trigger collapse of the world's industrial economy in as little as three weeks.

The supply disruptions to which Korowicz refers include water, food and oil. We can add financial credit to the list. In other words, credit could dry up as it nearly did in late 2008. Or the bond markets could trigger hyperinflation. California could have insufficient water to grow enough food to support much of the US, and not long from now. The list goes on.

Go into detail about what you're seeing as far as indications of abrupt climate change.

When I'm in the midst of a speaking tour, as I am now, I deliver a presentation approximately every day. Lately, I include a [different] indication of abrupt climate change [in] each presentation. In other words, I've been coming across evidence every day.

Recent examples include the June 19, 2015, paper in Science Advances: We are in the midst of the sixth great extinction. According to the abstract, the "sixth mass extinction is already under way." The lead author, in an interview, said, "life would take many millions of years to recover, and our species itself would likely disappear early on."

According to data from The Cryosphere Today, Arctic ice extent declined 340,000 square kilometers between June 17 and 18, 2015. Such an event is unprecedented. We could witness an ice-free Arctic by September of this year for the first time in human history.

How much temperature increase, over what period of time?

Depending upon the timing of economic collapse and release of the 50-gigaton burst of methane Natalia Shakhova warns about, earth could warm an additional 3 degrees Celsius within 18 months. The relatively slow rate of planetary warming we're seeing so far exceeds the ability of organisms to adapt by a factor of 10,000, according to a paper in the August 2013 edition of Ecology Letters.

We depend upon a living planet for our survival. We're killing non-human species at an astonishing rate. To believe we're clever enough to avoid extinction is pure hubris.

Is there an historical precedent for this phenomenon?

There is no historical precedent for ongoing planetary warming. We're dumping carbon into the atmosphere at a rate faster than the Great Dying from about 250 million years ago. That time, nearly all life on earth was driven to extinction.

What does this mean for humans? How do we cope and survive?

Astonishingly, against cosmological odds, you and I get to live. But not forever. And not much longer.

Coping with the reality of abrupt climate change and human extinction is hardly an easy undertaking. The message I've been delivering for several years is a heavy burden. I suggest fully absorbing the message that we get to live! Part of the process of living is death.

In addition to my latest book [Extinction Dialogs], co-authored by Carolyn Baker, I've developed other means for dealing with reality. Among these are a book for young adults co-authored by Pauline Schneider and a workshop co-developed and facilitated by Ms. Schneider. We signed a contract for the book in mid-June and the workshop is described at onlyloveremains.org.

What are some events of late you can point to as evidence that we are already experiencing abrupt climate change?

In addition to the information presented above, there's the ongoing collapse of the Larsen ice shelves in Antarctica, abundant evidence we're headed for a warmer year than 2014 (the hottest year in history), and numerous extreme weather events. These ongoing phenomena have been anticipated for years.

And now, they're here.

What are other factors you feel people should be aware of?

We're in serious human-population overshoot. We're driving to extinction at least 150 species each day. Nuclear power plants require grid-tied electricity, cooling water and people getting paychecks. Without all these, they melt down, thus immersing all life on earth in ionizing radiation.

There's more. Much more. But all the evidence points toward our individual deaths and the extinction of our species in the near future.

But most importantly, we get to live now.

Reporter's note: After my last Climate Disruption Dispatch article was published, I began receiving emails from people sharing their experiences with climatological aberrations they have been seeing where they live. Their experiences have ranged from witnessing vanishing glaciers, to creeks that have never dried up now vanishing, to record temperatures, to extremely early harvesting seasons for fruit. If you would like to send me information about what you're witnessing, so that I might include it in a future report, please share your experience (and photos, if you have them) with me: dahr@truthout.org