Supplement 3. Raw and analyzed charcoal data for the past 3000 years for Raven, Uchugrak, Poktovik, and Little Isac lakes.

File List LI07_charData.csv LI07_charParams.csv LI07_charResults.csv PO07_charData.csv PO07_charParams.csv PO07_charResults.csv RA07_charData.csv RA07_charParams.csv RA07_charResults.csv UC07_charData.csv UC07_charParams.csv UC07_charResults.csv Description For each site, three files provide the raw input data, the parameters used, and the output data for charcoal analysis via the program CharAnalysis (see ‘Methods’ in main text). File names reference site codes: LI (Little Isac), PO (Poktovik), RA (Raven), and UC (Uchugrak). The “*_charResults.csv” files has data on fire return intervals and smoothed fire frequency removed, given that these calculations were done outside of the program and do not reflect the time intervals given in the *_charParams.csv files. Missing values denoted by -9999 (*_charParams.csv) or NaN (*_charResults.csv). **07_charData.csv includes the following raw data (by column): cmTop: top depth (cm) of the sample cmBot: bottom depth (cm) of the sample ageTop: estimated age at top of sample (cal. yr before CE 1950) ageBot: estimated age at bottom of sample (cal. yr before CE 1950) charVol: volume of sediment subsample from which charcoal was prepared (cm3) charCount: pieces of charcoal counted in the sample (#) Checksum values: LI07_charData.csv: 192 rows (with headers), 6 columns Column 3 (ageTop (yr BP)): 313963 Column 6 (charCount (#)):1586 PO07_charData.csv: 234 rows (with headers), 6 columns Column 3 (ageTop (yr BP)): 438415 Column 6 (charCount (#)): 823 RA07_charData.csv: 302 rows (with headers), 6 columns Column 3 (ageTop (yr BP)): 448677 Column 6 (charCount (#)): 556 UC07_charData.csv: 393 rows (with headers), 6 columns Column 3 (ageTop (yr BP)): 534182 Column 6 (charCount (#)): 543 **07_charParams.csv: See CharAnalysis User’s Guide for description of parameters file, available at the web site linked to above. Checksum values: LI07_charParams.csv: 26 rows (with headers), 5 columns Column 3 (Parameters): -49519.821 PO07_ charParams.csv: 26 rows (with headers), 5 columns Column 3 (Parameters): -52975.821 RA07_ charParams.csv: 26 rows (with headers), 5 columns Column 3 (Parameters): -5199.821 UC07_ charParams.csv: 26 rows (with headers), 5 columns Column 3 (Parameters): -51479.821 **07_charResults.csv includes the following derived data (reflecting interpolation) cmTop_i: top depth (cm) of interpolated sample ageTop_i: bottom depth (cm) of interpolated sample charCount_i: pieces of charcoal in interpolated sample charVol_i: volume of interpolated sample charCon_i: charcoal concentration in interpolated sample (pieces/cm3) charAcc_i: charcoal accumulation rate, based in interpolated concentration and age (pieces/cm2*yr) charBkg: background charcoal, Cback, smoothed based on methods selected in *_charParams.csv file, (pieces/cm2*yr) charPeak: peak charcoal, Cpeak, based on methods selected in *_charParams.csv file, (pieces/cm2*yr) thresh1: threshold value (pieces/cm2*yr) based on first threshold entered in *_charParams.csv file thresh2: same as thresh1, but for second threshold entered thresh3: same as thresh1, but for third threshold entered threshFinalPos: positive threshold value (pieces/cm2*yr), based on fourth threshold value entered in *charParams.csv file. threshFinalNeg: negative threshold value (pieces/cm2*yr), based on fourth threshold value entered in *charParams.csv file. SNI: signal-to-noise index values, based on threshdFinalPos values. threshGOF: P value from KS goodness-of-fit test between fitted noise distribution and empirical data below the sample-specific threshold. peaks1: samples that exceed thresh1 values are identified by “1”; only the first sample is identified. peaks2: same as peaks1, but for the second threshold value peaks3: same as peaks1, but for the third threshold value peaksFinal: same as peaks1, but for the final threshold value peaksInsig.: peaks that exceeded threshFinalPos (the final threshold), but did not pass the minimum-count test are identified with a “1” peakMag: peak magnitude is the total pieces of charcoal accumulated in a given peak (pieces/cm2*peak); if a peak is only one sample long, then peak magnitude is simply CHAR minus the positive threshold. If a peak is more than one sample long, then each sample exceeding threshFinal is summed. Checksum values: LI07_charResults.csv: 206 rows (with headers), 21 columns Column 2 (age Top_i): 301965 Column 6 (char Acc_i): 9.139 Column 19 (peaks Final): 14 PO07_charResults.csv: 206 rows (with headers), 21 columns Column 2 (age Top_i): 301965 Column 6 (char Acc_i): 4.5649 Column 19 (peaks Final): 12 RA07_charResults.csv: 206 rows (with headers), 21 columns Column 2 (age Top_i): 301965 Column 6 (char Acc_i): 3.1762 Column 19 (peaks Final): 17 UC07_charResults.csv: 206 rows (with headers), 21 columns Column 2 (age Top_i): 301965 Column 6 (char Acc_i): 3.655 Column 19 (peaks Final): 24

文件列表：LI07_charData.csv、LI07_charParams.csv、LI07_charResults.csv、PO07_charData.csv、PO07_charParams.csv、PO07_charResults.csv、RA07_charData.csv、RA07_charParams.csv、RA07_charResults.csv、UC07_charData.csv、UC07_charParams.csv、UC07_charResults.csv

针对每个研究位点，均包含三个文件，分别对应通过CharAnalysis（炭粒分析程序）开展炭屑分析所需的原始输入数据、所用参数文件以及输出结果数据，具体说明参见正文“研究方法”部分。文件名中的前缀对应研究位点代码：LI代表Little Isac，PO代表Poktovik，RA代表Raven，UC代表Uchugrak。带"*_charResults.csv"后缀的文件包含经移除的火灾返回间隔与平滑火灾频率数据，此类计算均在CharAnalysis程序外部完成，无法反映"*_charParams.csv"文件中给定的时间间隔。缺失值分别以"-9999"（适用于"*_charParams.csv"文件）与"NaN"（适用于"*_charResults.csv"文件）表示。

"*_charData.csv"包含以下原始数据（按列说明）：
cmTop：样品顶部深度（单位：厘米）；cmBot：样品底部深度（单位：厘米）；ageTop：样品顶部的估算年龄（校准年，距公元1950年）；ageBot：样品底部的估算年龄（校准年，距公元1950年）；charVol：用于制备炭屑分析样品的沉积物分样体积（单位：立方厘米）；charCount：样品中统计的炭屑颗粒数（单位：个）。

校验值信息如下：
LI07_charData.csv：含表头共192行，6列；第3列（ageTop，距1950年校准年）校验值为313963，第6列（charCount，炭屑颗粒数）校验值为1586。
PO07_charData.csv：含表头共234行，6列；第3列校验值为438415，第6列校验值为823。
RA07_charData.csv：含表头共302行，6列；第3列校验值为448677，第6列校验值为556。
UC07_charData.csv：含表头共393行，6列；第3列校验值为534182，第6列校验值为543。

"*_charParams.csv"文件的参数说明可参见CharAnalysis用户指南，该指南可通过前文提及的网站获取。
校验值信息如下：
LI07_charParams.csv：含表头共26行，5列；第3列（参数列）校验值为-49519.821。
PO07_charParams.csv：含表头共26行，5列；第3列校验值为-52975.821。
RA07_charParams.csv：含表头共26行，5列；第3列校验值为-5199.821。
UC07_charParams.csv：含表头共26行，5列；第3列校验值为-51479.821。

"*_charResults.csv"包含以下衍生数据（均经过插值处理）：
cmTop_i：插值后样品的顶部深度（单位：厘米）；ageTop_i：插值后样品的底部深度（单位：厘米）；charCount_i：插值后样品中的炭屑颗粒数；charVol_i：插值后样品的体积（单位：立方厘米）；charCon_i：插值后样品的炭屑浓度（单位：颗粒/立方厘米）；charAcc_i：基于插值后浓度与年龄计算的炭屑积累速率（单位：颗粒/平方厘米·年）；charBkg：背景炭屑浓度（记为Cback），基于"*_charParams.csv"文件中选定的方法进行平滑处理，单位：颗粒/平方厘米·年；charPeak：峰值炭屑浓度（记为Cpeak），基于"*_charParams.csv"文件中选定的方法进行平滑处理，单位：颗粒/平方厘米·年；thresh1：基于"*_charParams.csv"文件中输入的第一阈值得到的阈值参数（单位：颗粒/平方厘米·年）；thresh2：与thresh1定义一致，对应输入的第二阈值；thresh3：与thresh1定义一致，对应输入的第三阈值；threshFinalPos：基于"*_charParams.csv"文件中输入的第四阈值得到的正阈值参数（单位：颗粒/平方厘米·年）；threshFinalNeg：基于"*_charParams.csv"文件中输入的第四阈值得到的负阈值参数（单位：颗粒/平方厘米·年）；SNI：信噪比指数，基于threshFinalPos参数计算得到；threshGOF：基于拟合噪声分布与样本阈值以下的实测数据进行Kolmogorov-Smirnov（KS）拟合优度检验得到的P值；peaks1：超过thresh1阈值的样品标记为“1”，仅标记首个符合条件的样品；peaks2：与peaks1定义一致，对应第二阈值；peaks3：与peaks1定义一致，对应第三阈值；peaksFinal：与peaks1定义一致，对应最终阈值；peaksInsig.：超过threshFinalPos（最终阈值）但未通过最小计数检验的峰值标记为“1”；peakMag：峰值强度指某一峰值区间内累计的炭屑总颗粒数（单位：颗粒/平方厘米·峰值区间）；若峰值仅对应单个样品，则峰值强度为该样品炭屑颗粒数减去正阈值；若峰值对应多个样品，则将所有超过最终阈值的样品的炭屑颗粒数求和。

校验值信息如下：
LI07_charResults.csv：含表头共206行，21列；第2列（ageTop_i）校验值为301965，第6列（charAcc_i）校验值为9.139，第19列（peaksFinal）校验值为14。
PO07_charResults.csv：含表头共206行，21列；第2列校验值为301965，第6列校验值为4.5649，第19列校验值为12。
RA07_charResults.csv：含表头共206行，21列；第2列校验值为301965，第6列校验值为3.1762，第19列校验值为17。
UC07_charResults.csv：含表头共206行，21列；第2列校验值为301965，第6列校验值为3.655，第19列校验值为24。