Improving Earth’s Magnetic Field Measurements by Numerical Corrections of Thermal Drifts and Man-Made Disturbances

<div>(a) Without temperature compensation, the difference between PLM and BDV scalar values (<i>B</i><sub>Diff</sub>) is temperature-dependent and varying between −30 nT to +50 nT. (b) After temperature compensation, the <svg height="11.8174pt" id="M3" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -8.6359 23.7474 11.8174" width="23.7474pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M578 512C578 619 494 650 387 650H140L134 622C219 615 223 609 210 542L127 119C112 40 104 34 23 28L17 0H235C317 0 387 7 444 33C515 65 564 122 564 195C564 289 495 335 412 352V354C505 373 578 422 578 512ZM486 510C486 422 423 367 314 367H257L294 565C299 591 305 602 315 608C324 614 339 617 362 617C421 617 486 595 486 510ZM466 200C466 100 393 35 296 35C222 35 198 51 212 127L250 333H303C388 333 466 303 466 200Z" id="g113-67"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.748,3.132)"><path d="M43 650V617C122 612 130 606 130 522V128C130 44 122 37 34 32V0H275C400 0 497 25 573 82C652 142 698 229 698 350C698 445 662 518 613 565C549 625 456 650 327 650H43ZM217 544C217 580 220 591 229 599C240 607 264 613 311 613C380 613 437 599 482 570C561 523 598 436 598 336C598 177 511 40 324 40C248 40 217 61 217 135V544Z" id="g58-66"></path></g><g transform="matrix(.0091,0,0,-0.0091,14.518,3.132)"><path d="M138 535C169 535 191 560 191 589C191 620 168 644 139 644S85 620 85 589C85 560 110 535 138 535ZM257 0V30C192 35 185 43 185 109V453C142 435 94 422 40 414V386C101 378 104 372 104 311V109C104 41 97 35 33 30V0H257Z" id="g58-103"></path></g><g transform="matrix(.0091,0,0,-0.0091,17.021,3.132)"><path d="M100 439H52L25 408L28 396H100V106C100 41 92 35 31 30V0H250V29C188 37 181 41 181 106V396H372V107C372 40 365 37 309 29V0H537V29C461 37 453 40 453 106V396H564C576 403 579 428 574 439H453V469C452 558 462 604 474 623S500 656 527 656C562 656 589 634 608 615C619 604 628 607 639 615C647 622 658 633 661 641C666 653 664 664 656 674C637 696 609 708 572 710C528 703 483 682 439 638C418 661 380 685 320 688C269 683 230 666 190 633C139 593 122 550 113 525S100 476 100 451V439ZM372 439H181V461C181 530 194 571 211 598C226 621 248 643 287 643C343 643 379 607 400 578C391 561 384 546 381 529C376 510 372 486 372 457V439Z" id="g58-26"></path></g></svg> decreased one order of magnitude (to about 5 nT maximum during the freezing temperatures). The data were obtained in February with −12 to +17°C temperature swing.</div>

Journal of Sensors

fig7

Figure 7

Figure 7: Improving Earth’s Magnetic Field Measurements by Numerical Corrections of Thermal Drifts and Man-Made Disturbances 