(Just two sites reporting for Sunday, as we are commencing an exercise to calibrate the sensors to a higher standard using a specially mixed calibration gas. There will be a ‘reduced service’ until that is completed).
On Easter Sunday the CBD site (Petrie Terrace) had its lowest average daily carbon dioxide concentration of the year so far – 441 ppm. Could this be the result of a public holiday and a weekend reducing vehicle emissions in the city? Perhaps. The 4th graph is traffic data for the whole Brisbane area for seven days from last Monday (from TomTom). Reduced travel time on Friday, Saturday and Sunday may be indexing reduced traffic (although it may also be that people tend not to drive as far as on regular weekdays). TomTom’s data is for the entire metro region, so the fact that Bellbird Park was also low generally fits with this explanation, though if there was a disproportionately larger drop in traffic in the CBD, and if winds were low enough not to unduly homogenise the concentrations from across the city, it would fit even better. We would need separate traffic counts in the different sites to see if this explanation really holds water, but it illustrates the kind of question this project could shed some light on.
We’re growing the network – if you’d like to host or sponsor a sensor – leave us a message. As we add more sensor sites, comparisons across the urban area will become more robust and informative about Brisbane’s Carbon dioxide emissions.
Daily Averages
For reference, latest monthly average (Feb 2023) from CSIRO for Kennaook/Cape Grim in NW Tasmania was 415.1 ppm. (Note – these are provisional values, subject to revision folllowing sensor re-calibrations and other checks.)
| DATE | Petrie Terrace | Chapel Hill | Bellbird Park | O’Reilly’s |
| 09 Apr 2023 | 441 ppm | — | 425 ppm | — |
| 08 Apr 2023 | 450 ppm | — | 425 ppm | 399 ppm |
| 07 Apr 2023 | 464 ppm | — | 446 ppm | 406 ppm |
| 06 Apr 2023 | 453 ppm | 432 ppm | 441 ppm | 404 ppm |
| 05 Apr 2023 | 462 ppm | 442 ppm | 445 ppm | 403 ppm |
| 04 Apr 2023 | 461 ppm | 431 ppm | 434 ppm | 406 ppm |
| 03 Apr 2023 | 456 ppm | 435 ppm | 433 ppm | 405 ppm |
| 02 Apr 2023 | 461 ppm | 437ppm | 418 ppm | 404 ppm |
| 01 Apr 2023 | 471 ppm | 446 ppm | 456 ppm | 407 ppm |
| 31 Mar 2023 | 462 ppm | 431 ppm | 439 ppm | TBA |
| 30 Mar2023 | 465 ppm | 433 ppm | 437 ppm | TBA |
| 29 Mar 2023 | 482 ppm | 451 ppm | 446 ppm | 417 ppm |
| 28 Mar 2023 | 476 ppm | 446 ppm | 450ppm | 423 ppm |
| 27 Mar 2023 | 470 ppm | 443 ppm | 445 ppm | 425 ppm |
| 26 Mar 2023 | 464 ppm | 439 ppm | 435 ppm | 417 ppm |
| 25 Mar 2023 | 467 ppm | 446 ppm | 437 ppm | TBA |
| 24 Mar 2023 | 475 ppm | 443ppm | 456 ppm | TBA |
| 23 Mar 2023 | 472 ppm | 444 ppm | 428 ppm | TBA |
| 22 Mar 2023 | 463 ppm | 435 ppm | 423 ppm | TBA |
| 21 Mar 2023 | 459 ppm | 431 ppm | 425 ppm | TBA |
| 20 Mar 2023 | 464 ppm | 441 ppm | 439 ppm | TBA |
| 19 Mar 2023 | 467 ppm | — | 445 ppm | TBA |
| 18 Mar 2023 | 471 ppm | 448 ppm | 443 ppm | TBA |
| 17 Mar 2023 | 477 ppm | 448 ppm | 443 ppm | TBA |
| 16 Mar 2023 | 484 ppm | 455 ppm | 470 ppm | TBA |
| 15 Mar 2023 | 468 ppm | 446 ppm | 444 ppm | TBA |
| 14 Mar 2023 | 461 ppm | 443 ppm | 446 ppm | 413 ppm |
| 13 Mar 2023 | — | 447 ppm | 440 ppm | |
| 12 Mar 2023 | — | 452 ppm | 446 ppm | |
| 11 Mar 2023 | — | 447 ppm | 449 ppm | |
| 10 Mar 2023 | — | 443 ppm | 420 ppm | |
| 9 Mar 2023 | 470 ppm | 435 ppm | 436 ppm | |
| 8 Mar 2023 | 461 ppm | 427 ppm | 418 ppm | |
| 7 Mar 2023 | 452 ppm | 424 ppm | 427 ppm | |
| 6 Mar 2023 | 454 ppm | 428 ppm | 432 ppm | |
| 5 Mar 2023 | 450 ppm | 426 ppm | 430 ppm | |
| 4 Mar 2023 | 449 ppm | 425 ppm | 424 ppm | |
| 3 Mar 2023 | 456 ppm | 432 ppm | 427 ppm | |
| 2 Mar 2023 | 465 ppm | 434 ppm | 423 ppm | |
| 1 Mar 2023 | 452 ppm | 425ppm | 426 ppm | |
| 28 Feb 2023 | 453 ppm | 429 ppm | 429 ppm | |
| 27 Feb 2023 | 458 ppm | 432 ppm | 437 ppm | |
| 26 Feb 2023 | 455 ppm | 434 ppm | 440 ppm | |
| 25 Feb 2023 | 454 ppm | 432 ppm | 435 ppm | |
| 24 Feb 2023 | 452 ppm | 428 ppm | 423 ppm | |
| 23 Feb 2023 | 454 ppm | 428 ppm | 421 ppm | |
| 22 Feb 2023 | 457 ppm | 433 ppm | 425 ppm | |
| 21 Feb 2023 | 463 ppm | 437ppm | 429 ppm | |
| 20 Feb 2023 | 460 ppm | 438 ppm | 425 ppm | |
| 19 Feb 2023 | 459 ppm | 434 ppm | 430 ppm | |
| 18 Feb 2023 | 463 ppm | 436 ppm | 438 ppm | |
| 17 Feb 2023 | 466 ppm | 437 ppm | 443 ppm | |
| 16 Feb 2023 | 459 ppm | 435 ppm | 438 ppm | |
| 15 Feb 2023 | 459 ppm | 430 ppm | 426 ppm | |
| 14 Feb 2023 | 457 ppm | 431 ppm | 419 ppm | |
| 13 Feb 2023 | 453 ppm | 429 ppm | 418 ppm | |
| 12 Feb 2023 | 450 ppm | 428 ppm | 436 ppm | |
| 11 Feb 2023 | 448 ppm | 428 ppm | 435 ppm | |
| 10 Feb 2023 | 451 ppm | 429ppm | 418 ppm | |
| 9 Feb 2023 | 451 ppm | 428ppm | 413 ppm | |
| 8 Feb 2023 | 452 ppm | 429 ppm | 416 ppm | |
| 7 Feb 2023 | 454 ppm | 434 ppm | 434 ppm | |
| 6 Feb 2023 | 454 ppm | 436 ppm | 425 ppm | |
| 5 Feb 2023 | 454 ppm | 447 ppm | 433 ppm | |
| 4 Feb 2023 | 456 ppm | 451 ppm | 451 ppm | |
| 3 Feb 2023 | 464 ppm | 438 ppm | 442 ppm | |
| 2 Feb 2023 | 451 ppm | 426 ppm | 418 ppm | |
| 1 Feb 2023 | 460 ppm | — | 428 ppm | |
| 31 Jan 2023 | 459 ppm | — | 434 ppm | |
| 30 Jan 2023 | 454 ppm | 432 ppm | 432 ppm | |
| 29 Jan 2023 | 455 ppm | 437 ppm | 450 ppm | |
| 28 Jan 2023 | 470 ppm | 451 ppm | 449 ppm | |
| 27 Jan 2023 | 469 ppm | 452 ppm | 445 ppm | |
| 26 Jan 2023 | 470 ppm | 451 ppm | 449 ppm | |
| 25 Jan 2023 | 470 ppm | 440 ppm | 436 ppm | |
| 24 Jan 2023 | 460 ppm | 436 ppm | 433 ppm | |
| 23 Jan 2023 | 455 ppm | 435 ppm | 441 ppm | |
| 22 Jan 2023 | 448 ppm | 433 ppm | 433 ppm | |
| 21 Jan 2023 | 450 ppm | 431 ppm | 425 ppm | |
| 20 Jan 2023 | 453 ppm | 431 ppm | 421 ppm | |
| 19 Jan 2023 | 451 ppm | 430 ppm | 436 ppm | |
| 18 Jan 2023 | 451 ppm | 431 ppm | 421 ppm | |
| 17 Jan 2023 | 453 ppm | 436 ppm | 422 ppm | |
| 16 Jan 2023 | 460 ppm | 440 ppm | 425 ppm | |
| 15 Jan 2023 | 456 ppm | 436 ppm | 432 ppm | |
| 14 Jan 2023 | 452 ppm | 431 ppm | 422 ppm | |
| 13 Jan 2023 | 455 ppm | 433ppm | 422 ppm | |
| 12 Jan 2023 | 452 ppm | 433 ppm | 433 ppm | |
| 11 Jan 2023 | 453 ppm | 433 ppm | 442 ppm | |
| 10 Jan 2023 | 453 ppm | 435 ppm | 424 ppm | |
| 9 Jan 2023 | 447 ppm | 427 ppm | 426 ppm | |
| 8 Jan 2023 | 450 ppm | 434 ppm | 439 ppm | |
| 7 Jan 2023 | 449 ppm | 436 ppm | 439 ppm | |
| 6 Jan 2023 | 450 ppm | 435 ppm | 429 ppm | |
| 5 Jan 2023 | 468 ppm | 443 ppm | 437 ppm | |
| 4 Jan 2023 | 454 ppm | 431 ppm | 440 ppm | |
| 3 Jan 2023 | 450 ppm | 436 ppm | 436 ppm | |
| 2 Jan 2023 | 448 ppm | 431 ppm | 423 ppm | |
| 1 Jan 2023 | 451 ppm | 436 ppm | 422 ppm |