LDEO Seismology: Long-Period Noise

Z47A-TA , LHE

Noise Levels at Different Periods

The table below gives the decibel 10% noise level (in db) for each month in several period bands. The 10% noise level is defined as the signal level not exceeded 10% of the time, based on hourly measurements. Each entry in the table is color coded with reference to the New Low Noise Model (NLNM, Peterson, 1993):
navy, -6 db < value-NLNM < -3 db
blue, -3 db < value-NLNM < 3 db
aqua, 3 db < value-NLNM < 6 db
lime, 6 db < value-NLNM < 9 db
yellow, 9 db < value-NLNM < 12 db
orange, 12 db < value-NLNM < 15 db
red, 15 db < value-NLNM < 20 db
fuchsia, 20 db < value-NLNM < 25 db
silver, value-NLNM < -6 db, value-NLNM > 25 db

Black indicates that there was an insufficient number of hourly measurements to calculate a noise level.

Noise levels (PSD) in decibels
Month Chan. Qual. # obs. 268s 228s 193s 164s 139s 118s 100s 85s 72s 61s 52s 44s 37s 32s 27s 23s 19s 16s 14s 12s 10s

201204 LHE AR 168 -155 -155 -156 -157 -157 -158 -160 -161 -162 -164 -166 -168 -170 -172 -173 -170 -163 -158 -154 -154 -156

201203 LHE AR 96 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201202 LHE AR 336 -147 -147 -149 -151 -151 -153 -154 -155 -156 -158 -160 -161 -163 -163 -164 -165 -161 -156 -153 -153 -151

201201 LHE AR 24 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201110 LHE AR 24 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201109 LHE AR 117 -147 -148 -149 -150 -151 -153 -155 -156 -157 -159 -162 -163 -164 -165 -165 -164 -160 -157 -155 -154 -152

201108 LHE AR 24 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201107 LHE AR 96 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201105 LHE AR 208 -151 -152 -153 -154 -155 -155 -157 -158 -160 -162 -163 -164 -166 -166 -166 -166 -164 -161 -159 -157 -155

Month	Chan.	Qual.	# obs.	268s	228s	193s	164s	139s	118s	100s	85s	72s	61s	52s	44s	37s	32s	27s	23s	19s	16s	14s	12s	10s
201204	LHE	AR	168	-155	-155	-156	-157	-157	-158	-160	-161	-162	-164	-166	-168	-170	-172	-173	-170	-163	-158	-154	-154	-156
201203	LHE	AR	96	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201202	LHE	AR	336	-147	-147	-149	-151	-151	-153	-154	-155	-156	-158	-160	-161	-163	-163	-164	-165	-161	-156	-153	-153	-151
201201	LHE	AR	24	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201110	LHE	AR	24	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201109	LHE	AR	117	-147	-148	-149	-150	-151	-153	-155	-156	-157	-159	-162	-163	-164	-165	-165	-164	-160	-157	-155	-154	-152
201108	LHE	AR	24	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201107	LHE	AR	96	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201105	LHE	AR	208	-151	-152	-153	-154	-155	-155	-157	-158	-160	-162	-163	-164	-166	-166	-166	-166	-164	-161	-159	-157	-155