基于 Deep Flare Net 的可操作太阳耀斑预测模型

Operational solar flare prediction model using Deep Flare Net

Website of operational DeFN showing a full-disk solar image and detected ARs, in addition to the full-disk forecasts, region-by-region forecasts, an alert mark, and a comment list (https://defn.nict.go.jp)

Abstract

We developed an operational solar flare prediction model using deep neural networks, named Deep Flare Net (DeFN). DeFN can issue probabilistic forecasts of solar flares in two categories, such as ≥ M-class and < M-class events or ≥ C-class and < C-class events, occurring in the next 24 h after observations and the maximum class of flares occurring in the next 24 h. DeFN is set to run every 6 h and has been operated since January 2019. The input database of solar observation images taken by the Solar Dynamic Observatory (SDO) is downloaded from the data archive operated by the Joint Science Operations Center (JSOC) of Stanford University. Active regions are automatically detected from magnetograms, and 79 features are extracted from each region nearly in real time using multiwavelength observation data. Flare labels are attached to the feature database, and then, the database is standardized and input into DeFN for prediction. DeFN was pretrained using the datasets obtained from 2010 to 2015. The model was evaluated with the skill score of the true skill statistics (TSS) and achieved predictions with TSS = 0.80 for ≥ M-class flares and TSS = 0.63 for ≥ C-class flares. For comparison, we evaluated the operationally forecast results from January 2019 to June 2020. We found that operational DeFN forecasts achieved TSS = 0.70 (0.84) for ≥ C-class flares with the probability threshold of 50 (40)%, although there were very few M-class flares during this period, and we should continue monitoring the results for a longer time. Here, we adopted a chronological split to divide the database into two for training and testing. The chronological split appears suitable for evaluating operational models. Furthermore, we proposed the use of time-series cross-validation. The procedure achieved TSS = 0.70 for ≥ M-class flares and 0.59 for ≥ C-class flares using the datasets obtained from 2010 to 2017. Finally, we discuss the standard evaluation methods for operational forecasting models, such as the preparation of observation, training, and testing datasets and the selection of verification metrics.

我们利用深度神经网络开发了一个可操作的太阳耀斑预测模型,命名为深耀斑网(deep flare Net, DeFN)。DeFN可以对观测后24小时内发生的≥m级和< m级事件或≥c级和< c级事件以及未来24小时内发生的最大级别两类太阳耀斑进行概率预报。DeFN每6小时运行一次,自2019年1月开始运行。太阳动力观测台(SDO)拍摄的太阳观测图像输入数据库是从斯坦福大学联合科学行动中心(JSOC)运营的数据存档中下载的。利用多波长观测数据,从磁图中自动检测出活动区域,并在每个区域中近乎实时地提取出79个特征。将火炬标签附加到特征数据库中,然后将数据库标准化并输入到DeFN中进行预测。DeFN使用2010年至2015年获得的数据集进行预训练。用真实技能统计(TSS)的技能得分对模型进行评估,得出≥m级耀斑的TSS = 0.80,≥c级耀斑的TSS = 0.63的预测结果。为了比较,我们对2019年1月至2020年6月的运营预测结果进行了评估。我们发现,对于≥c级耀斑,DeFN预报的TSS = 0.70(0.84),概率阈值为50(40)%,尽管在此期间m级耀斑很少,我们应该继续监测更长时间的结果。在这里,我们采用了按时间顺序划分的方法,将数据库分为训练和测试两个部分。按时间顺序划分似乎适合于评估操作模型。此外,我们建议使用时间序列交叉验证。使用2010 - 2017年获得的数据集,该程序获得≥m级耀斑的TSS = 0.70,≥c级耀斑的TSS = 0.59。最后,我们讨论了业务预测模型的标准评估方法,如观测、训练和测试数据集的准备,以及验证指标的选择。

Fig. 1

Flowchart of operational DeFN. It is executed using the NRT data and the pretrained model. The best-performing model among the models trained using the 2010--2015 datasets is chosen as the pretrained model

Fig. 2

Full solar disk vector magnetograms taken by HMI/SDO on 6 September 2017. a HMI definitive series data for the full disk and the areas detected by DeFN with red frames. b HMI NRT data showing the HARP areas in gray scale and the areas detected by DeFN. Note that both HARP and DeFN areas overlapped each other. If DeFN areas are outside the HARP areas, the data are set to zero

相关推荐
uncle_ll1 分钟前
PyTorch图像预处理:计算均值和方差以实现标准化
图像处理·人工智能·pytorch·均值算法·标准化
宋138102797202 分钟前
Manus Xsens Metagloves虚拟现实手套
人工智能·机器人·vr·动作捕捉
SEVEN-YEARS5 分钟前
深入理解TensorFlow中的形状处理函数
人工智能·python·tensorflow
世优科技虚拟人9 分钟前
AI、VR与空间计算:教育和文旅领域的数字转型力量
人工智能·vr·空间计算
tatasix10 分钟前
MySQL UPDATE语句执行链路解析
数据库·mysql
cloud studio AI应用15 分钟前
腾讯云 AI 代码助手:产品研发过程的思考和方法论
人工智能·云计算·腾讯云
南城花随雪。23 分钟前
硬盘(HDD)与固态硬盘(SSD)详细解读
数据库
儿时可乖了24 分钟前
使用 Java 操作 SQLite 数据库
java·数据库·sqlite
懒是一种态度26 分钟前
Golang 调用 mongodb 的函数
数据库·mongodb·golang
禁默26 分钟前
第六届机器人、智能控制与人工智能国际学术会议(RICAI 2024)
人工智能·机器人·智能控制