After John wrote the abstract "通过黄土高原西部平凉剖面的植硅体分析,对黄土高原西部全新世中晚期气候进行研究,将研究时期的气候分为5个阶段:8.43～7.78KaB.P.,气候凉湿；7.78～7.17KaB.P.,气候暖湿；7.17～6.27KaB.P.,气候总体仍为暖湿,但较上带有变冷趋势；6.27～5.55KaB.P.,气候特征为凉湿；5.55～0KaBP.,气候特征仍为凉湿,但具有偏凉干趋势.明显的气候波动与全新世中晚期全球变化可以对比,与相邻区域的孢粉、粒度、磁化率等研究工作结果较为一致.", he wrote these keywords "中全新世, 古气候, 平凉剖面, 黄土高原". Do you think his choice of keywords was correct? Answer yes or no.
yes