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We studied Lyman-$\alpha$ (Ly$\alpha$) escape in a statistical sample of 43Green Peas with HST/COS Ly$\alpha$ spectra. Green Peas are nearby star-forminggalaxies with strong [OIII]$\lambda$5007 emission lines. Our sample is fourtimes larger than the previous sample and covers a much more complete range ofGreen Pea properties. We found that about 2/3 of Green Peas are strongLy$\alpha$ line emitters with rest-frame Ly$\alpha$ equivalent width $>20$ \AA.The Ly$\alpha$ profiles of Green Peas are diverse. The Ly$\alpha$ escapefraction, defined as the ratio of observed Ly$\alpha$ flux to intrinsicLy$\alpha$ flux, shows anti-correlations with a few Ly$\alpha$ kinematicfeatures -- both the blue peak and red peak velocities, the peak separations,and FWHM of the red portion of the Ly$\alpha$ profile. Using propertiesmeasured from SDSS optical spectra, we found many correlations -- Ly$\alpha$escape fraction generally increases at lower dust reddening, lower metallicity,lower stellar mass, and higher [OIII]/[OII] ratio. We fit their Ly$\alpha$profiles with the HI shell radiative transfer model and found Ly$\alpha$ escapefraction anti-correlates with the best-fit $N_{HI}$. Finally, we fit anempirical linear relation to predict Ly$\alpha$ escape fraction from the dustextinction and Ly$\alpha$ red peak velocity. The standard deviation of thisrelation is about 0.3 dex. This relation can be used to isolate the effect ofIGM scatterings from Ly$\alpha$ escape and to probe the IGM optical depth alongthe line of sight of each $z>7$ Ly$\alpha$ emission line galaxy in the JWSTera.

Ly$\alpha$ profile, dust, and prediction of Ly$\alpha$ escape fraction in Green Pea Galaxies