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Unraveling the short‐term behavior of the Earth's past geomagnetic field at regional scales is crucial for understanding its global behavior and, thus, the dynamics of the deep Earth. In this context, obtaining accurate full‐vector geomagnetic field records from regions where archeomagnetic data are absent becomes essential. Here, we present the first full‐vector archeomagnetic data from Central Asia, derived from the analysis of nine archeological kilns sampled in South Uzbekistan, dating back to the period between 200 BCE and 1429 CE. To obtain these new data, we conducted thermal and alternating field demagnetization procedures, along with Thellier‐Thellier paleointensity experiments, including partial thermoremanent magnetization checks, thermoremanent magnetization anisotropy and cooling rate corrections. The comparison between the new data, previous selected data from Central Asia, and available global models reveals important differences between approximately 400 BCE and 400 CE, especially concerning the geomagnetic field intensity element. In order to investigate this in detail, we have developed a regional update of the SHAWQ global models family by incorporating, for the first time, high‐quality data from Central Asia. The results suggest that this deviation is linked to non‐dipolar sources of the geomagnetic field in Central Asia reaching a maximum contribution around the first century BCE. According to the updated global paleoreconstruction, this non‐dipole feature, manifested at the Earth's surface as low intensities, is associated with the presence of a reversed flux patch at the core‐mantle boundary beneath this region. The geomagnetic field is a global feature that changes over time and space. These changes are known over the last few centuries through direct observations collected by satellites and geomagnetic observatories. However, indirect measurements, based on the paleomagnetic study of archeological and geological materials, are needed to disentangle geomagnetic field behavior over longer time scales. In this context, archeomagnetism is the discipline that studies the direction and strength of the past geomagnetic field by investigating the magnetic properties of well dated archeological baked clay material. In order to properly describe the behavior of the Earth's magnetic field it is crucial to have a good temporal and spatial coverage of archeomagnetic data. In this work, we present the first full‐vector archeomagnetic data for Central Asia, a large region that remained unexplored from an archeomagnetic point of view. The new data were obtained from 9 kilns excavated in South Uzbekistan, with ages ranging from 200 BCE to 1429 CE. We then developed a regional update of the SHAWQ global models family by incorporating, for the first time, high‐quality archeomagnetic data from Central Asia. The results indicate a relevant non‐dipole feature presented over this region around the first century BCE. First nine full‐vector archeomagnetic data for Central Asia for the last 2k yearsResults indicate a large non‐dipole contribution around the first century BCE in Central AsiaCentral Asia intensity data reveal a reversed flux patch at the core‐mantle boundary First nine full‐vector archeomagnetic data for Central Asia for the last 2k years Results indicate a large non‐dipole contribution around the first century BCE in Central Asia Central Asia intensity data reveal a reversed flux patch at the core‐mantle boundary

Recent paleomagnetic studies have shown that important short‐lived intensity fluctuations occurred during the first millennium BCE. However, the knowledge of the spatial and temporal extension of these features is still limited by the scarce availability of robust data. In this study we focus on the study of the intensity decrease that took place in Central Asia during the second half of the 1st millennium BCE after the high intensities that characterized the Levantine Iron Age Anomaly. Since previous archeointensities available for this period and region were obtained without accomplishing modern standards of quality, we present here new archeointensities that are derived from classical Thellier and Thellier experiments, including partial thermoremanent magnetization (pTRM) checks, thermoremanent magnetization (TRM) anisotropy and cooling rate corrections at the specimen level. The new 51 archeointensities, together with previous archeointensities, have been used to present a new local paleosecular variation curve for Central Asia. The results confirm the existence of an important geomagnetic field intensity decrease in South Uzbekistan from the 4th century BCE to the end of the 1st century BCE associated with rates of changes up to −15 μT/century. A critical analysis of the archeointensity global database indicates that this feature was present at continental scale, from Western Europe to Central Asia. However, this trend is not identified in other regions such as Japan or Mexico. Finally, the comparison with the dipole moment derived from recent global geomagnetic field reconstructions suggests a strong influence of non‐dipolar sources upon this continental intensity feature. The Earth's magnetic field (also called the geomagnetic field) is continuously changing over time and space. Since the 19th century, the behavior of the geomagnetic field is known through direct observations performed in geomagnetic observatories and satellites. However, the only way to recover past geomagnetic field in ancient times is through paleomagnetic and archeomagnetic studies. In particular, archeomagnetism is the study of heated archeological materials, which include ferromagnetic particles acting as a compass and recording the geomagnetic field direction and strength at a certain time. When the archeological material cools down the ferromagnetic particles save the direction and intensity, like a photograph of the ancient geomagnetic field. Nowadays, there are very few archeomagnetic studies dealing with archeological materials from Central Asia. In this work, we present the variation of the geomagnetic field intensity between 600 BCE–600 CE in Uzbekistan deduced from a complete archeomagnetic investigation of 70 pottery fragments. The results confirm a rapid variation of geomagnetic field strength between 400 BCE and 100 BCE–1CE. To determine the spatial expression of this feature, we compared the obtained trend for Central Asia with the geomagnetic field intensity evolution in other regions of the world. We present 51 new thermoremanent magnetization‐anisotropy corrected archeointensities for South UzbekistanAn important decrease in intensity is observed between 400 BCE and 100 BCE–1 CE, probably associated with non‐dipolar sourcesSimilar intensity V‐shaped trends are observed at continental scale We present 51 new thermoremanent magnetization‐anisotropy corrected archeointensities for South Uzbekistan An important decrease in intensity is observed between 400 BCE and 100 BCE–1 CE, probably associated with non‐dipolar sources Similar intensity V‐shaped trends are observed at continental scale