The 1200-year Climate Podcast in Detail

LISTEN: 1,200 Years of Earth’s Climate, Transformed into Sound By Danielle Venton

(N.B. The title above on KQED’s site is misleading because the video shown is from 1680 – 2016.)


When Philippe Tortell, a Professor of Oceanography at U British Columbia and Director of the Peter Wall Institute of Advanced Studies, got in touch with me in 2016 he wanted to know if it’s possible to hear the new climate “quantum state.” He  suggested a long-span climate sonification project with ice core records as a possible data source. While previously doing some sonification of financial data of the last 50 years, on a lark, I’d put the USA GDP side-by-side with CO2 records from Mauna Loa and had easily noticed a tight sonic correlation. A blip in time when compared what Philippe was suggesting and we began gathering the longer record with the help of glaciologist Garry Clarke, also of UBC. We were going to listen to the recent “blip” in its context of hundreds of thousands of years of preceding climate.

A group of graduate students at UC Berkeley approached me with the same interest. They’d been assigned to work with non-academic partners, in their case KQED Science, and were interested “to develop a ~6 to 7  minute radio program to help viewers ‘see’ the causes and impacts of climate change through music.” Their project focused squarely on the recent “blip.” And as one commented during our work together, “When you sonify data, you experience time in a way you can’t when you look at a chart.”

Data and Production Team for KQED Podcast

UC Berkeley: Valeri Vasquez, Kate Pennington and Hal Gordon
KQED: Danielle Venton and Kat Snow


Sound (48 kHz, 16bit) — long version, 850 – 2016, 1166 years in 5 minutes


Sound (48 kHz, 16bit) — shorter version, 1760 – 2016, 256 years in approx. 1 minute


Video  — KQED version, 1680 – 2016, 336 years in approx. 1 1/2 minutes


Data Sources (850 – 2016)

The temperature data used in the composition is annual mean Northern Hemisphere temperature anomaly from tree ring, sediment and other sources. See Moberg, A. et al. “Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data”, Nature (2005)

The dataset is available online in the supplementary information document nature03265-s6.doc at

The first column gives the annual temperature deviations starting at year 1 and running to 1979. After 1979, non-proxy data is taken from NASA , GISS Surface Temperature Analysis (GISTEMP), which provides estimates of surface temperature change at

Northern Hemisphere annual means from 1980 – 2016 were used. The column is ‘J-D’ which is the January to December average.

The CO2 data used in the composition is provided from Ammann, C. et al. “Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model”, PNAS (2007)

For a description of the article’s supplementary information, see

Gas concentrations up until the most recent four years (2013 – 2016) were taken from the file co2.dat at

And the remaining four years from the Mauna Loa Observatory

Sound Generation

Sounds are synthesized from a physical model of a plucked nylon string guitar (temperature) and a frequency modulation singing voice synthesis (CO2). Both are coded in the Faust DSP language.

Data is read in, scaled, and mapped to synthesis parameters using the Chuck computer music language. The whole process can either run in real time or write the final stereo .wav file faster than real time. A Chuck sonification intro is available at


Ice Core Walk, with Philippe Tortell, Garry Clarke, George Hilley, Greg Niemeyer, Liz Carlisle

A 3km sound walk listening directly to long-span data from 3km deep ice cores (800,000 years).