It’s Complicated: Reporting on science in a changing

media landscape

Ivan Semeniuk

Science & Media: When Worlds Collide…

The multimillennial sea-level commitment of global warming

Abstract: Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m °C−1 and 1.2 m °C−1 of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m °C−1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales.

Levermann et al, PNAS July 15, 2013

Seas may rise 2.3 meters per degree of global warming: report

Sea levels could rise by 2.3 meters for each degree Celsius that global

temperatures increase and they will remain high for centuries to come, according to a new study by the leading climate research institute, released on Monday.

Anders Levermann said his study for the Potsdam Institute for Climate Impact Research was the first to examine evidence from climate history and combine it with computer simulations of contributing factors to long-term sea-level increases: thermal expansion of oceans, the melting of mountain glaciers and the melting of the Greenland and Antarctic ice sheets.

Scientists say global warming is responsible for the melting ice. A U.N. panel of

scientists, the IPCC, says heat-trapping gases from burning fossil fuels are nudging up temperatures. A small number of scientists dismiss human-influenced global warming, arguing natural climate fluctuations are responsible.

"We're confident that our estimate is robust because of the combination of physics

and data that we used," Levermann told Reuters. "We think we've set a benchmark for how much sea levels will rise along with temperature increases."

(Reuters – TGAM, The Guardian, Sydney Morning Herald, Huffington Post)

Sea level rise: that ship has sailed

Like an ocean liner that takes time to start moving but then can’t easily be stopped, sea level rise due to global warming is a reality that humans will be dealing with for centuries to come a new study warns.

Casting an eye forward two thousand years, the study finds that Earth is effectively committed to

about 2.3 metres of sea level rise for every degree Celsius that the planet warms above its preindustrial temperature.

Even if fossil fuel use were to end today, the authors say, inertia in the Earth’s climate system will

keep up the ocean’s inevitable advance because of the physical expansion of water and the ongoing melting of glaciers and ice sheets —phenomena that will persist far into the future because of the greenhouse gasses that have already been added to the atmosphere.

"We're confident that our estimate is robust because of the combination of physics and data that

we used," said Anders Levermann, a climate scientist at the Potsdam Institute for Climate Impact Research in Germany and the lead author of the study, published Monday in the Proceedings of the National Academy of Sciences.

The study is the first to project sea level rise based on past climate history combined with computer

models of climate change. In general, climate scientists are in broad agreement that sea level rise is an unavoidable consequence of climate change, but predictions vary as to the degree and rate of rising waters.

What makes it news writing?

• It’s “new”. (And on deadline)

• Facts presented objectively and with attribution.

• Editorial independence.

You know you’re a journalist when:

Input Output

Sources Stories

Sources Stories

Bu$iness Realities

Sources Stories

Journalistic Ethics

Bu$iness Realities

Ethics*

• Seek truth and report it

• Minimize harm

• Act Independently

• Be accountable

*Society of Professional Journalists

Science media is everywhere – but not necessarily journalism

News = {Significant} U {Interesting}

News = {Significant} U {Interesting}

Why This? Why Now?

Why This? Why Now?

• Peg (something just happened, is happening)

Why This? Why Now?

• Peg (something just happened, is happening)

• Interesting

Why This? Why Now?

• Peg (something just happened, is happening)

• Interesting

• New to readers

Why This? Why Now?

• Peg (something just happened, is happening)

• Interesting

• New to readers

• Tension

Why This? Why Now?

• Peg (something just happened, is happening)

• Interesting

• New to readers

• Tension

• Significant (beyond the immediate field)

Why This? Why Now?

• Peg (something just happened, is happening)

• Interesting

• New to readers

• Tension

• Significant (beyond the immediate field)

Audiences & Outlets:

Professionally Interested

Audiences & Outlets:

Professionally Interested

Casually Interested

Audiences & Outlets:

Professionally Interested

Casually Interested

Casually Disinterested

A brief history of science journalism:

• early 1900’s – major US newspapers begin regular coverage of science as “progressive”

• 1934 – Nat. Assoc. of Science Writers formed to improve coverage/profile of science in society

• 1945 – NYT science writer William Laurence covers Manhattan project while also writing press releases for the war department (this was not considered a conflict of interest!)

• 1949 – “what counts most is recognition from scientists themselves” – George Gray, Time magazine science correspondent upon winning award from AAAS

A brief history of science journalism:

• 1957 – launch of Sputnik 1 leads to massive infusion of resources in science and education in the US and across the west generally

• 1962 – Rachel Caron’s Silent Spring takes the shine off scientific progress – science journalists offer conflicted reactions

• 1969 – 1st manned moon landing broadcast to the world on live television

• 1974 – NYT science section and NOVA begins • 1975 – CIA experiments on psychiatric patients in US and

Canada become public • 1979 – accident at Three Mile Island nuclear plant • 1986 – Challenger space shuttle disaster raises questions

about NASA

Now about climate

Change…

Climate change & the US media 2005 – 2006

Climate change & the US media 2005 – 2006

2007 - 2008

2009 - 2010

2009 - 2010

Science journalists’ dilemma…

Anthropogenic climate change is real and likely to have a significant impact (consensus view = “truth”).

But…

Questions that keep me awake…

• How much can extreme weather today be linked to climate change?

• How credible is the IPCC on the threat?

• Are all the consequences of climate change bad?

• Do carbon credits work?

• Is adaptation to change more realistic than switching from hydrocarbons?

• Is geo-engineering viable?

Questions that keep me awake…

• Why has global temperature level off for past 15 years?

NYT (Jan 13) – “What to make of a warming plateau?”

The Economist (April) – “Apocalypse maybe later”

National Post (LS) – “…the overwhelming consensus may be cracking.”

A case in point…

Meanwhile in Canada…

Something to think about…

• http://www.smithsonianmag.com/video/Climate-Change-101-With-Bill-Nye-the-Science-Guy.html

• http://www.youtube.com/watch?v=xcVwLrAavyA

• http://www.theglobeandmail.com/technology/technology-video/video-high-tech-frozen-lab-giving-scientists-insight-into-the-arctic-ocean/article9832958/

• http://vimeo.com/69122809#

Thank you!

tgam.ca/semeniuk

@ivansemeniuk