The impact that climate change will have on the world is what makes it such a crucial issue, and makes it important to understand. Consequently, when I have asked scientists what the situation is with climate change this year, some have given me an explanation based on the effects that they’ve seen or expect.
I’ve gathered these answers together as the last group of explanations that I’m summarizing in the Simple Climate end of year polls. These polls are a way for you to help me with one of the aims of my blog – producing a single, simple explanation of climate change. Please read them and then vote for your favourite and/or comment at the end. Also, if you haven’t already voted in them, the first three polls are still ongoing. The first includes direct explanations of the physics underlying climate change, the second one-line and metaphorical explanations, and the third includes attempts to explain it at a personal level. The winner from each poll will then go into a final poll-to-end-all-polls at the end of the year. Happy voting!
Huw Griffiths, marine scientist, British Antarctic Survey, Cambridge, UK
Antarctica is one of the best places if you want to observe real changes due to human impact. In the West Antarctic 90% of the glaciers that are on land are retreating. We’ve seen surface waters warming, we’ve seen sea ice reducing every summer. Our physical scientists tell me that it’s linked to human activity, as in the amount of CO2 being released into the atmosphere, directly affecting the temperature and weather systems surrounding the Antarctic.
Jane Ferrigno, geologist, US Geological Survey, Reston, US
I have been looking at historical and remotely sensed data of Antarctica for more than 30 years. The major changes in the ice shelves in the Antarctic Peninsula are recent, beginning about 20 years ago, with the change beginning in the north of the Peninsula. When I see this amount of ice melt, the evidence points to warming.
Barry Sinervo, evolutionary biologist, University of California, Santa Cruz, US
All animals are adapted to critical thermal limits from millions of years of evolution and they simply cannot adapt fast enough to current rates of climate change. They live in specific thermal habitats to which they are adapted. Near some parts of their range it is too hot – that is what we call the thermal limit of a species. These thermal limits are moving rapidly and squeezing lizards to the limit.
Too many individuals have to die to accomplish the process of adaptation. Adaptation is based on natural selection, which involves survival of the most fit – i.e. high body temperature in the case of climate warming – and selective death of others – e.g. low body temperature forms. Right now too many individuals are dying selective deaths to sustain a positive values of population replacement. In many areas this is driving populations into negative values of population replacement which pushes them to lower and lower numbers, given that climate warming is relentless, eventually culminating in extinction.
Nick Polato, marine biologist, Penn State University, Pennsylvania, US
I think that most people really don’t understand how drastic the effect of increasing ocean temperatures will be on coral reefs. In Florida where I do a lot of my field work, reefs have been on a steady decline for decades. And while it is still a beautiful place to dive, when I talk to people who were diving there twenty or thirty years ago it is clear that we are now only seeing a shadow of what it used to be. I think that since marine environments are largely out of sight and out of mind the general public is basically unaware of what is being lost. Reefs matter because they protect shorelines from erosion, provide habitat for many species that we rely on for food, and harbor species that contain unique chemical compounds that we might be able to use to develop new drugs.
George Somero, marine scientist, Stanford University, Palo Alto, US:
The on-going increases in global temperature are sufficient to have significantly perturbing effects on individual species and these effects will lead to modifications of numerous ecosystems. The rate at which temperatures are rising is unprecedented and may out-strip the ability of the processes of adaptation to “keep up with” warming.
John Moore, paleoclimatologist, Beijing Normal University, China/University of Lapland/University of Oulu, Finland:
Sea level rise over the last 200 years has been measured. It’s the highest we have seen. There are only two possible explanations since we know that the oceans will expand on heating and that warmer temperatures result in less ice. 1: The Earth’s temperature is warmer now than at any point in the 200 years, or 2: the ocean basins are reducing in area. We know 2: is not happening. Hence the world is warming. In fact the response of the sea level is actually better linked to the climate forcing from greenhouse gases, aerosols, volcanism and solar forcing than it is to global temperature.
Bill Morris, biologist, Duke University, Durham, US:
With more greenhouse gases in the atmosphere, we will have a warmer world with altered patterns of precipitation. Both of these changes will alter where each species can live.