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We present the results of a program that monitored the near-IR spectroscopicvariability of a sample of 19 embedded protostars. Spectra were taken on timeintervals from 2 days to 3 years, over a wavelength range from 0.85 {\mu}m to2.45 {\mu}m, for 4-9 epochs of observations per target. We found that thespectra of all targets are variable, and that every emission feature observedis also variable (although not for all targets). With one exception, there wereno drastic changes in the continua of the spectra, nor did any line completelydisappear, nor did any line appear that was not previously apparent. Thisanalysis focuses on understanding the connection between accretion (traced by HBr $\gamma$ and CO) and the wind (traced by He I, [FeII], and sometimes H$_2$).For both accretion and wind tracers, the median variability was constant versustime interval between observations, however the maximum variability that weobserved increased with time interval between observations. Extinction isobserved to vary within the minimum sampling time of 2 days, suggestingextinguishing material within a few stellar radii at high disk latitudes. Thevariability of [FeII] and H$_2$ were correlated for most (but not all) of the 7YSOs showing both features, and the amplitude of the variability depends on theveiling. Although the occurrence of CO and Br $\gamma$ emission are connected,their variability is uncorrelated, suggesting that these emissions originate inseparate regions near the protostar (e.g., disk and wind).

Near-IR Spectroscopic Monitoring of Class I Protostars: Variability of Accretion and Wind Indicators